MARINE BIOLOGY - SHINE

FORUM TOPIC (Chapter 14, Page 323 - Critical Thinking Q2)

2007-12-02T22:56:00.000-08:00

Scientists predict that the ocean will get warmer and the sea level will rise as a result of an intensified greenhouse effect. How might this affect coral reefs?

A prediction of how global warming will affect the marine environment is that the flow of some major ocean currents may change, affecting many marine ecosystems. Already stressed ecosystems such as mangrove forests and estauries will be flooded; coral reefs may not grow fast enough to keep up with rising sea levels.

CITE

Marine Biology Sixth Edition - Peter Castro/Michael E. Huber

Living in a Greenhouse: Our Warming Earth, pages 406 & 407

Coral Reefs Assignment - Chapter 14, Part II

2007-12-02T20:35:00.000-08:00

Differences
1. Fringing reefs are reefs that form along a coastline.
2. Barrier reefs grow parallel to shorelines, but farther out, usually separated from the land by a deep lagoon.
3. Coral Atolls are rings of coral that grow on top of old, sunken volcanoes in the ocean.
4. Fringing reefs grow on the continental shelf in shallow water.
5. Coral Atolls begin as fringe reefs surrounding a volcanic island; then, as the volcano sinks, the reef continues to grow, and eventually only the reef remains.

Similarities
1. Spur-and-groove formations develop primarily on reef slopes that are exposed to consistent strong winds which are found on atolls and some fringing reefs as well as barrier reefs.
2. All grow different types of corals
3. All consist of a reef flat and a reef slope
4. All are home to many different types of fishes
5. All are type of coral reefs

CITE
http://www.glennevanish.com/Saipan/saipan-map.gif
http://www.enchantedlearning.com/subjects/ocean/Coralreef.shtml

Coral Reefs Assignment - Chapter 14, Part I

2007-12-02T20:01:00.000-08:00

ATOLLS

BARRIER REEFS

FRINGE REEFS

1. How is each reef structure formed? “Coral” is a general term for several different groups of cnidarians, only some of which help build reefs. In reef-building, or hermatypic, corals the polyps produce calcium carbonate skeletons. Billions of these tiny skeletons form a massive reef. The most important reef builders are a group known as scleractinian corals, sometimes called the stony or “true” corals. Nearly all reef-building corals contain symbiotic zooxanthellae that help the corals make their calcium carbonate skeletons. It is the zooxanthellae as much as the corals themselves that construct the reef framework, and without zooxanthellae there would be no reefs.

2. Where is each reef structure found? There are three basic types of coral reefs; fringing, barrier and atoll. Fringing reefs are located very close to shore, and because of water run off they are typically high in nutrients and the water has a high turbidity. Barrier reefs are further from shore, with a lagoon between the reef and the shore. And finally atolls are a circular reef with a central lagoon and possibly small islands formed on the reef.

3. What is the trophic structure of a reef? The trophic structure of a reef is the recycling of nutrients. Coral reefs have among the highest rate of nitrogen fixation of any natural community. Coral reefs are very productive even though the surrounding ocean water lacks nutrients because nutrients are recycled extensively, nitrogen is fixed on the reef, and the zooplankton and nutrients that occur in the water are used efficiently. The reef is able to provide some of its own nutrients.

4. How does the location and type of reef influence the trophic structure? It is theorised that each of these types of reefs corresponds to a differing age of the entire reef structure. The youngest is the fringing reef, with the corals colonising a shallow water area close to the land. If the sea levels then rise or the land subsides, then the reef structure keeps up with this changing depth by growing upward. Eventually a shallow area with no coral growth will form behind the main reef, called a lagoon, giving a barrier reef. If the sea level or land subsides so much as to cause the land to disappear below the water surface, then an atoll is formed. The overall type of the reef whether it is a turbid, high nutrient reef where the stony corals are less common and algae abounds or crystal clear, low nutrient reef where the stony corals can dominate, is dependent of several factors. These include the proximity to land (therefore water run off which will be high in nutrients), proximity to river mouths (for the same reason as land proximity), and location of deep sea currents (which typically bring nutrient rich water. Each type of reef is also divided into various zones within each reef.

5. Give examples of the types of corals found on reefs. Corals are divided into two kinds and both are stationary on the ocean bottom. Hard corals such as brain, star, staghorn, elkhorn and pillar corals have rigid exoskeletons, or corallites, that protect their soft delicate bodies. Gorgonians, or soft corals, such as sea fans, sea whips, and sea rods, sway with the currents and lack an exoskeleton.

6. Give examples of competition, predation, and grazing. Competition – Sessile coral reef organisms must compete for space. Corals and seaweeds compete for light as well. The two main ways in which corals compete for space are by overgrowing their neighbors and by directly attacking them. NOTES FOR STUDENT ONLY: Competition – The interaction that results when a resource is in short supply and one organism uses the resource at the expense of another. Predation – Predation on corals occur when a variety of animals eat corals, but instead of killing the coral and eating it entirely, most coral predators eat individual polyps or bite off pieces here and there. The coral colony as a whole survives and can grow back the portion that was eaten. NOTES FOR STUDENT ONLY: Predation – The act of an animal, or predator, eating another organism, or prey. A top predator is one that feeds at the top of the food chain. Grazing – Grazing is the process of transplantation, removal and caging. An example of the effects of grazing on reefs are damselfishes. Many damselfishes graze on seaweeds inside territories that they vigorously defend, chasing away other fishes that happen to venture inside. Many such damselfishes has actually “farm” their territories. NOTE FOR STUDENT ONLY: Grazer – An organism that feeds primarily on plants.

CITE
Marine Biology Sixth Edition, Peter Castro/Michael E. Huber - Chapter 14http://ozreef.org/library/articles/zonation.html
http://www.reefrelief.org/coral_reef_body.shtml

http://library.thinkquest.org/4305/coral.jpg
http://images.encarta.msn.com/xrefmedia/sharemed/targets/images/pho/t044/T044158A.jpg http://cache.eb.com/eb/image?id=20213&rendTypeId=4
http://z.about.com/d/animals/1/7/Z/C/GreatBarrierReef-EO.JPG.jpg
http://library.thinkquest.org/05aug/00183/Great%20Barrier%20Reef_image005.jpg
http://www.caribbeanedu.com/images/kewl/atoll.jpg
http://www.adventuresinbelize.com/packages/southerncayes/atoll-ariel.jpg

Fish Resources - The Fate of the Ocean

2007-12-02T16:55:00.000-08:00

The article on The Fate of the Ocean is 12 pages long and I would like more people to read it because it explains the importance of marine organisms in our daily lives as well as the abuse that we humans create for ourselves in the upcoming years. It is an informative article that is easy to understand. It also provides a lot of detailed explanation of how science works around us and how our actions affect marine life.

In this article, Scientists stated that, "From a scientific perspective, we now know enough to improve dramatically the conservation and management of marine systems through the implementation of ecosystem-based approaches." This statement is self explanatory to all but the problem is getting full cooperation from everyone. "Change" has always been close to impossible for many, which is why by the time people understand the importance of marine organisms, it is already to late. SAD, but TRUE!

I love the ending of this article which read, "AT NO TIME IN HUMAN HISTORY has so much scientific inquiry been focused so intensively in one direction: on the anthropogenic changes in our world. As a result, we are learning more, and more quickly then ever before, about the life-support systems of earth work. Science now recognizes that the ocean is not just a pretty vista or a distant horizon but the vital circulatory, respiratory, and reproductive organs of our planet, and that these biological systems are suffering. Much effective treatment is suggested by computer-modeling studies, which the Bush administration, with its fear of science, negates-even though computer models are the same powerful tools that enable us to put men into space, to run wars, and to forecast financial trends." In comparison of this statement, the Marianas, a perfect example of how powerful politicians can be, is the act of our former Governor, Governor Babauta, making the stateless individuals U.S. citizens. If only our politicians would concentrate on the more important matters, EDUCATION and HEALTH, anything can be accomplished!

While reading this article, I kept thinking, what if we completely stop the exporting of wild seafood around the world? Could this be a possible solution to some of the problems? My thoughts continued and came up with, no more exporting wild seafood = more tourists visiting places where wild seafood is overflowing = revenue = growth in wild seafood production. For example, if I am a wild seafood lover and one way to indulge in seafood is to visit a place where seafood is served daily, then I will definitely go there. I wish it was this simple!

CITE

The Last Days of the Ocean
News: We're Pushing Our Seas to the Brink. Can They be Saved? A Mother Jones special report. March/April 2006 Issue

Fish Resources - "Only 50 Years Left" For Sea Fish

2007-12-02T15:45:00.000-08:00

I think the article on “Only 50 Years Left” For Sea Fish make a whole lot of sense to me. One reason why I agree with the article is that my father was a fisherman his whole life and today I have three brothers that not only enjoys fishing as a sport but catches fish for food. The catch that my brothers have today even when combined does not even come close to the amount of fish that my father caught 25 years ago. One of the wonderful memories I have of my father when I was as young as 10 years old is when he goes out fishing from night until dawn and returns home with a truck load of fish. Not a cooler full of fish, but, a truck load of fish. Growing up I remembered that people were very generous and neighbors always help each other. When my father returns home from fishing, we already have all our neighbors waiting for their share of the catch, free of charge. With this type of generosity, all our neighbors would also share either their vegetables or animals (pigs, chickens, ducks, cows, goats) with us.

As stated by Steve Palumbi, Scientist from Stanford University, “Unless we fundamentally change the way we manage all the ocean species together, as working ecosystems, then this century is the last century of wild seafood.” I totally agree with his statement because without the cooperation of everyone, the abuse with fishing will continue not forever but rather only until all the wild seafood are gone which is not long from today.

For the Marianas, I will have to say that it will be very sad when the fish population do decline as predicted. Why? Well, one, because some of our people were born fishermen and they fish today for profit as their only way of making ends meet. Two, fish has always been a delicacy for our people and we could not imagine not having fish as part of our diet. An example would be, every year, during lent, we eat only seafood, mainly fish, everyday for 45 days until Easter Sunday. This has always been the practice for my family as part of our religion, Roman Catholics. Therefore, I believe that if people here in the Marianas were educated on the importance of our marine environment as well as to establish strict laws when dealing with our marine organisms, then wild seafood may still be saved and 50 years from today, everyone will enjoy what has always been enjoyed in the past, FISHING!

CITE:

By Richard Black

Environment correspondent, BBC News website

Last Updated: Thursday, 2 November 2006, 19:01 GMT

Sea Floor Spreading

2007-11-26T23:44:00.000-08:00

What is sea floor spreading? Sea-floor spreading is the process by which new sea floor is formed as it moves away from spreading centers in mid-ocean ridges.

What are some of the major land forms that are created from plate movement? Trenches, Mid-Ocean Ridges, Mountains & Volcanoes.

How were the Mariana Islands formed? The Mariana Islands were formed by volcanoes.

What evidence exists today that the plates are still moving and that the islands are ancient volcanoes? Plate Tectonics! The earth beneath our feet is not dead; it is constantly moving, driven by forces deep in its core. Nor is the planet's crust all of one piece; it is composed of numerous plates, which are moving steadily in relation to one another. This movement is responsible for all manner of phenomena, including earthquakes, volcanoes, and the formation of mountains. All these ideas, and many more, are encompassed in the concept of plate tectonics, which is the name for a branch of geologic and geophysical study and for a powerful theory that unites a vast array of ideas. Plate tectonics works hand in hand with several other striking concepts and discoveries, including continental drift and the many changes in Earth's magnetic field that have taken place over its history. No wonder, then, that this idea, developed in the 1960s but based on years of research that preceded that era, is described as "the unifying theory of geology."

What is an atoll? An atoll is a coral reef that develops as a ring around a central lagoon.

Why are atolls mainly found on the Pacific? Because atoll formation requires coral reef building, atolls are limited to tropical waters. Atolls are most commonly found in the Pacific and Indian Oceans.

CITES:
http://www.eoearth.org/article/Atoll.
http://www.answers.com/topic/plate-tectonics?cat=technology

Chapter 2 - Level 2 Quiz

2007-11-23T15:24:00.000-08:00

Fish of the Marianas Waters

2007-11-14T18:50:00.000-08:00

CN: Mahi Mahi SN: Coryphaenidae Hippurus

CN: Bluespine Unicornfish or Tataga SN: Naso Unicornis

CN: Atulai SN: Selar Crumenophthalmus

CN: Bluefin Trevally SN: Caranx Melampygus

CN: Malabar Trevally or Eiei SN: Carangoides Malabaricus

CN: Parrotfish or Palakse SN: Cheilinus Digraammus

CN: Red Snapper or Onaga SN: Lutjanus Campechanus

CN: Rudderfish or Guilie SN: Centrolophus Niger

CN: Skipjack Tuna SN: Katsuwonus Pelamis

CN: Snapper or Gindai SN: Pristipomoides Zonatus

CN: Tagafi - Red Phase or Red Bass SN: Lutjanus Bohar

CN: Two-spot Red Snapper or Tagafi SN: Lutjanus Bohar

CN: Mutibar Goatfish or Satmoneti SN: Parupeneus Multifasciatus

CN: Striped Surgeonfish SN: Acanthurus Lineatus

CN: Star Puffer SN: Arothron Stellatus

CN: Lattice Soldierfish SN: Myripristis Violacea

CN: Sabre Squirrelfish SN: Sargocentron Spiniferum

CN: Orangespine Unicornfish SN: Naso Lituratus

CN: Manta Ray SN: Manta Birostris

CN: Great White Shark SN: Carcharodon Carcharias

CITES:

http://www.dfw.gov.mp/fisheries/fishfs.htm

http://www.seagrantfish.lsu.edu/biological/snapper/redsnapper.htm

http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=88bb24a0b2d699588b8be95912617de1&rgn=div8&view=text&node=50:9.0.1.1.2.2.1.2&idno=50

http://www.sea-ex.com/fishphotos/parrotfish.htm

http://www.sea-ex.com/fishphotos/dolphin.htm

http://www.cfsan.fda.gov/~frf/rfe2sk.html

http://www.catalogueoflife.org/show_common_name_details.php?name=Bluefin+trevally

http://fish.gov.au/fishnames/fishnames.php?pid=2493

http://www.catalogueoflife.org/show_common_name_details.php?name=Bluespine+unicornfish

http://www.catalogueoflife.org/show_common_name_details.php?name=Rudderfishhttp://www.botany.hawaii.edu/basch/uhnpscesu/htms/kahofish/fish_pops/mullid/goatfish06.htm

http://www.fishbase.org/Summary/SpeciesSummary.php?id=1417

http://zipcodezoo.com/Animals/S/Selar_crumenophthalmus.asp

http://affashop.gov.au/PdfFiles/28_fsr06_speciesnames.pdf

www.aasharks.com/.../great-white-shark.htm

library.thinkquest.org/5512/mantaray.htm

animal-world.com/encyclo/marine/tangs/naso.php

www.acclaimimages.com/.../marine_biology.html

www.ukdivers.net/life/redseaf.htmwww.d1.dion.ne.jp/.../itasan_diving_gakumei.html

http://www.scubatravel.co.uk/squirrelfish2.html

FORUM TOPIC (Chapter 1, Page 21)

2007-11-14T15:41:00.001-08:00

Critical Thinking – Question 2

In Chapter 1 it was explained that the statement “There are mermaids in the ocean” is not a valid scientific hypothesis. Can the same be said of the statement “There are no mermaids in the ocean”? Why?

Yes, I believe that the same can be said of the statement “There are no mermaids in the ocean” as the statement “There are mermaids in the ocean” because neither statement is testable.

I grew up being told beautiful stories of mermaids in the ocean therefore I believe that because marine biologists could not prove that there are no mermaids in the ocean does not mean that mermaids do not exist.

On the other hand, marine biologists may state that the statement “There are mermaids in the ocean” is a testable hypothesis since they have searched for a mermaid without success. A testable hypothesis is one that at least potentially can be proved false. In this case, they can prove that there are no mermaids in the ocean because they have not found a single mermaid.

SEE FORUMS (Chapter 3, Page 69)

2007-11-14T15:41:00.000-08:00

Critical Thinking - Question 2

Just for the fun of it, someone in Beaufort, South Carolina, throws a message in a bottle into the sea. Some time later, someone in Perth, on the west coast of Australia, finds the bottle. Referring to Figure 3.20 and fold-out map of this book, can you trace the path the bottle probably took?

The path the bottle probably took started from the warm currents of the Gulf Stream to the cold Canary Current where the winds would then take it to the Antarctic Circumpolar Current to where it was found in Perth, on the west coast of Australia.

This is very interesting. This reminds me a lot of one of my favorite shows; “Message In A Bottle” stars Kevin Kostner.

SEE FORUMS (Chapter 8, Page 179) - Questions

2007-11-13T21:41:00.001-08:00

Question 1.

The only living representatives of a very ancient group is the hagfishes and lampreys (jawless fishes). Why do you suppose these jawless fishes do not live in our waters?

Question 2.

A Marine Biologist from Fish & Wildlife collected a deep-water female shark containing 20 eggs from our waters for the first time and did a detailed study on it. Do you think that the Marine Biologist will conclude that this shark species, although new, belong to the family of sharks already present in our waters? Would it be possible that this new female shark mated with one of our male sharks? Please explain your answers.

Question 3.

Parrot fish is one of the favorite fish of the local people. What are the advantages and disadvantages should parrot fish have an equal number of males as females present in our waters?

SEE FORUMS (Chapter 8, Page 179)

2007-11-08T17:17:00.002-08:00

Critical Thinking - Question 3

Individuals of some species of bony fishes change sex, some to maintain more males than females, others more females than males. What are the advantages and disadvantages of each situation? Are there any advantages and disadvantages in having an equal number of males and females?

In the deep sea finding a mate can be difficult – even harder than finding food therefore being able to change from a male to a female or a female to a male is advantageous for these types of fishes because there would be an increase in reproduction. Deep-sea fishes that are hermaphrodites guarantee the ability to breed. In at least some species of anemone fishes (Amphiprion), all individuals begin as males. Each sea anemone is inhabited by a single large female that mates only with a large, dominant male. If the female disappear or is experimentally removed, her mate changes into a female and the largest of the non-breeding males becomes the new dominant male. Males of some wrasses form harems of many females. If the male disappears, the largest dominant female immediately begins to act like a male and within a relatively short period of time changes color and transforms into one that is capable of producing sperm. A variation of hermaphroditism among fishes is sex reversal, or sequential hermaphroditism, in which individuals begin life as males but change to females (protandry), or females change into males (protogyny). These changes are controlled by sex hormones but triggered by social cues such as the absence of a dominant male. I believe that there are neither advantages nor disadvantages in having an equal number of males and females since protandry and protogyny are present within these fishes. The way I understand it, we will never run out of fishes that are hermaphrodites.

SEE FORUMS (Chapter 8, Page 179)

2007-11-08T17:17:00.001-08:00

Critical Thinking - Question 2

A deep-water shark, new to science, is collected for the first time. The specimen is studied in detail, but its stomach is empty. How could you get a rough idea of its feeding habits? The specimen is a female, and its reproductive tract is found to contain 20 eggs. Can you tell the type of development characteristics of this species?

I think one can get a rough idea of an unidentified deep-water shark's feeding habits by studying the feeding habits of other known sharks. In addition, sharks possess movable powerful jaws that have rows of numerous sharp, often triangular teeth, therefore, if the unidentified deep-water shark possess any of these features, then we can assume that their feeding habits would be the same as the sharks known today.

Yes, it is possible to tell the development characteristic of the unidentified deep-water female shark by studying the 20 eggs found in its reproductive tract. Since the eggs were found in the reproductive tract of the unidentified deep-water shark then this shark could be ovoviviparous, which are cartilaginous fishes that retains eggs inside their reproductive tract for additional protection and gives birth to live young.

SEE FORUMS (Chapter 8, Page 179)

2007-11-08T17:17:00.000-08:00

Critical Thinking - Question 1

Hagfishes and lampreys are the only living representatives of a very ancient group. Why do you suppose there are still some of these jawless fishes around?

I suppose hagfishes and lampreys (jawless fishes) are still living today because of the simplicity of their way of life. Hagfishes feed mostly on dead or dying fishes while lampreys attach to other fishes and suck their blood or feed on bottom invertebrates. Both jawless fishes do not require much effort for survival.

Chapter 8 - Level 2 Quiz

2007-11-06T18:47:00.001-08:00

Chapter 7 - Level 2 Quiz

2007-11-06T18:47:00.000-08:00

Genetics/Cell Cycle

2007-10-23T04:34:00.000-07:00

1. What is DNA? DeoxyriboNucleic Acid.
2. What are the 4 bases? A (Adenine), T (Thymine), C (Cytosine) & G (Guanine).
3. What 2 peices of information did the scientists need to solve the elusive structure of DNA? In order to solve the elusive structure of DNA, a couple of distinct pieces of information needed to be put together. One was that the phosphate backbone was on the outside with bases on the inside; another that the molecule was a double helix. It was also important to figure out that the two strands run in opposite directions and that the molecule had a specific base pairing.
4. What are the specific base pairs? G can only bind to C and A can only bind to T.
5. How does the pairing rule effect the shape and structure of DNA? According to the biochemist Erwin Chargoff even though different organisms have different amounts of DNA, the amount of adenine always equals the amount of thymine. The same goes for the pair guanine and cytosine. For example, human DNA contains about 30 percent each of adenine and thymine, and 20 percent each of guanine and cytosine. With this information at hand James Watson was able to figure out the pairing rules. On the 21st of February 1953 he had the key insight, when he saw that the adenine-thymine bond was exactly as long as the cytosine-guanine bond. If the bases were paired in this way, each rung of the twisted ladder in the helix would be of equal length, and the sugar-phosphate backbone would be smooth.
6. What does the DNA do during cell division? During cell division, the DNA molecule is able to "unzip" into two pieces. One new molecule is formed from each half-ladder, and due to the specific pairing this gives rise to two identical daughter copies from each parent molecule.
7. How many base pairs does E. Coli have? How long does it take to replicate? How is the DNA packaged in the cell? The DNA in E. coli bacteria is made up of 4 million base pairs and the whole genome is thus one millimeter long. The single-cell bacterium can copy its genome and divide into two cells once every 20 minutes. In order to fit, the DNA must be packaged in a very compact form. In E. coli the single circular DNA molecule is curled up in a condensed fashion.
8. How many base pairs does Human DNA have? How long does it take to replicate? How is the DNA packaged in the cell? The DNA of humans is composed of approximately 3 billion base pairs, making up a total of almost a meter-long stretch of DNA in every cell in our bodies. The human DNA is packaged in 23 distinct chromosome pairs. Here the genetic material is tightly rolled up on structures called histones.

1. What is RNA? How different is it from DNA? RiboNucleic Acid. DNA is made up of double strand while RNA is made up of a single strand. Also the base T (Thymine) in DNA is replaced by U (Uracil) in RNA.
2. How are the RNA messages formed? The alphabet in the RNA molecule contains 4 letters, i.e. A, U, C, G. To construct a word in the RNA language, three of these letters are grouped together. This three-letter word are often referred to as a triplet or a codon. An example of such a codon is ACG. The letters don't have to be of different kinds, so UUU is also a valid codon. These codons are placed after each other in the RNA molecule, to construct a message, a RNA sequence. This message will later be read by the protein producing machinery in the body.
3. How are the RNA messages interpreted? Every organism has an almost identical system that is able to read the RNA, interpret the different codons and construct a protein with various combinations of the amino acids. In fact every RNA word or codon, corresponds to one single amino acid. These codons and their correlation with the amino acids in a protein sequence is what defines the genetic code.

1. Describe cell cycle. The cell cycle, or cell-division cycle, is the series of events that take place in a eukaryotic cell leading to its replication. These events can be divided in two broad periods: interphase—during which the cell grows, accumulating nutrients needed for mitosis and duplicating its DNA—and the mitotic (M) phase, during which the cell splits itself into two distinct cells, often called "daughter cells". The cell-division cycle is an essential process by which a single-celled fertilized egg develops into a mature organism, as well as the process by which hair, skin, blood cells, and some internal organs are renewed.
2. What is nuclear division. The division of the nucleus and its genetic information into more than one cell deriving from a parent cell, either via meiosis or mitosis.
3. What is interphase. A phase of the cell cycle, defined only by the absence of cell division. During interphase, the cell obtains nutrients, and duplicates its chromatids. Most eukaryotic cells spend most of their time in interphase.
4. Cytokinesis. Cytokinesis is the process whereby the cytoplasm of a single cell is divided to spawn two daughter cells. It usually initiates during the late stages of mitosis, and sometimes meiosis, splitting a binucleate cell in two to ensure that chromosome number is maintained from one generation to the next. In animal cells, one notable exception to the normal process of cytokinesis is oogenesis (the creation of an ovum in the ovarian follicle of the ovary), where the ovum takes almost all the cytoplasm and organelles, leaving very little for the resulting polar bodies, which then die. In plant cells, a dividing structure known as the cell plate forms across the centre of the cytoplasm and a new cell wall forms between the two daughter cells.

5. Homologous chromosomes. (Science: genetics) a pair of chromosomes containing the same linear gene sequences, each derived from one parent. The chromosomes tend to pair or synapse during meiosis. They have the same genes, in the same location, but the genes have different versions (not like in sister chromatids that are exact replicas).
Retrieved from "http://www.biology-online.org/dictionary/Homologous_chromosome"
This page has been accessed 20,188 times. This page was last modified 23:44, 19 March 2007.

6. Phases of mitosis (5 of them).
1. Prophase – In prophase, the chromatin condenses into discrete chromosomes. The nuclear envelope breaks down and spindles form at opposite "poles" of the cell.
2. Metaphase – In metaphase, the chromosomes are aligned at the metaphase plate (a plane that is equally distant from the two spindle poles).
3. Anaphase – In anaphase, the paired chromosomes (sister chromatids) move to opposite ends of the cell.
4. Telophase – In this last stage, the chromosomes are cordoned off in distinct new nuclei in the emerging daughter cells. Cytokinesis is also occurring at this time.
Interphase – G1 phase: The period prior to the synthesis of DNA. In this phase, the cell increases in mass in preparation for cell division. Note that the G in G1 represents gap and the 1 represents first, so the G1 phase is the first gap phase. S phase: The period during which DNA is synthesized.

7. Phases of meiosis and how it is different from mitosis.
Meiosis begins with Interphase I. During this phase there is a duplication genetic material, DNA replication. Cells go from being 2N, 2C (N= chromosome content, C = DNA content) to 2N, 4C. Cells remain in this active phase 75% of the time. The chromatin remains in a nuclear envelope while a pair of centrioles lies inside a centrosome.
During Prophase I, the chromatin condenses into chromosomes, the nuclear envelope disappears, and a spindle apparatus begins to form. Each chromosome consists of a pair of chromatids connected by a centromere. Cells are now 4N, 4C. The major occurrence in this phase is the coupling of these homologous chromosomes. Two double-stranded chromosomes form a four-stranded tetrad. In some cases, there is crossing-over of the two middle strands, at a site called the chiasma, such that there is genetic recombination. This process is extremely important for creating genetic diversity.
In Metaphase I, the tetrads line up on the "equator" of the cell. The centrosome has replicated and one has moved to each pole. Microtubules that extend out of each centrosome attach to kinetochores in the center of each side of the tetrads that have lined up on the equator.
Anaphase I occurs as the microtubules pull the pairs of homologous chromatids toward each pole, as the tetrad is divided. The cell begins to lengthen.
During Telophase I, the nuclear envelope begins to reform and nucleoli reappear. The cell begins to split, forming a cleavage furrow in the middle.
In Cytokinesis I, the cells finally split, with one copy of each chromosome in each one. Each of the two resulting cells is now 2N, 2C.
Interkinesis has not replication, unlike the previous Interphase I and the interphase of mitosis.Prophase II, Metaphase II, Anaphase II, and Telophase II repeats the same steps as Prophase I-Telophase I, with half as much genetic material.
Cytokinesis II is the final step of meiosis, where each cell splits into two daughter cells, for a total of four gametes, each with half the number of chromosomes. Each of the four resulting cells is 1N, 1C. (30)
In Meiosis the first phase is Interphase but in Mitosis it is last. In addition, Meiosis process are seven stages while Mitosis process are five phases.
8. Describe the process and purpose of crossing over. Crossing over occurs when the sperm and egg chromosomes pair up and swap genetic information, reducing the number of chromosomes to a complete set. It is important because it makes the number of chromosomes the normal number and also allows the genetic information to remain present in the cell.

CITES:
http://en.wikipedia.org/wiki/Cytokinesis
http://biology.about.com/od/mitosis/a/aa051206a.htm
http://www.biology-online.org/dictionary/Homologous_chromosome
http://en.wikipedia.org/wiki/Interphase
http://www.biology-online.org/dictionary/Nuclear_Division
http://en.wikipedia.org/wiki/Cell_cycle
http://nobelprize.org/educational_games/medicine/dna_double_helix/readmore.html

Virtual Dissection - Crayfish

2007-10-17T22:17:00.002-07:00

Internal anatomy of a crayfish: edible freshwater crustacean, with pincers on the two forelegs.

Encephalon: site of the mental functions of a crayfish.

Stomach: part of the digestive tract between the esophagus and the intestine.

Heart: blood-pumping organ of the crayfish.

Gonad: sex gland of a crayfish.

Extensor muscles: muscle that extends the tail of the crayfish.

Anus: outlet of the digestive tract.

Flexor muscle: muscle that bends the tail of the crayfish.

Digestive gland: glandular organ that produces digestive enzymes.

Ganglion of ventral nerve cord: budge related to a collection of nerves of the abdomen of a crayfish.

Ventral nerve cord: collection of nerves in the abdomen of a crayfish.

Maxilliped: pair of appendages of a crayfish used for holding prey.

Esophagus: part of the digestive tract between the mouth and the stomach.

Mandible: lower jaw.

Mouth: entrance to the digestive tract.

Green gland: antennary gland.

Eye: sight organ of a crayfish.

Taxonomy - Crayfish are members of the Decapod crustaceans.
External Anatomy

Reproduction

Female crayfish "In-berry".

Juvenile crayfish attached to the abdomen of a female.

CITES:
http://www.infovisual.info/02/025_en.html
http://crayfish.byu.edu/crayfish_biology.htm

Virtual Dissection - Squid

2007-10-17T22:17:00.001-07:00

External Morphology
1 – This is the squids's dorsal surface. 2 – This is the squids's mantle.
3 – This is the fin portion of the mantle.
4 – This is the collar portion of the mantle.
5 – This is an eye.
6 – This is one of ten arms.
7 – This is one of a pair of tentacles.

1 – This is the squid's lateral surface.
2 – This is the squids's mantle. 3 – This is the fin portion of the mantle.
4 – This is the collar portion of the mantle.
5 – This is an eye.
6 – This is one of ten arms.
7 – This is one of a pair of tentacles.

1 – This is the squid's ventral surface. 2 – This is the squids's mantle.
3 – This is the fin portion of the mantle.
4 – This is the collar portion of the mantle.
5 – This is an eye.
6 – This is one of ten arms.
7 – This is one of a pair of tentacles.
8 – This is the squid's funnel; the equivalent of the clam's excurrent siphon.
9 – This is an incision that was made in preparation for injecting the circulatory system of the squid.

Funnel Area
1 - This is the collar area of the squid's mantle.
2 – This is the squid's funnel.
3 – This is the squid's eye.
4 – The arrows point to the two funnel retractor muscles.
5 – The arrow points to the squid's rectum. The two small flaps are called rectal papillae.
6 – The left arrow points to one of a pair of cartilaginous ridges in the mantle that fits into grooves on the funnel (right arrow).

Buccal Mass
1 – The arrow points to a sucker on one of the squid's arms.
2 – This is a part of the buccal membrane.
3 – This is the buccal mass, a muscular organ with chitinous teeth and a radula for masticating prey to prepare it for digestion.
4 – The arrow points to tissues associated with the squid's salivary glands.
5 – The arrow points to the esophagus. The tissue surrounding the esophagus is associated with the liver.

Malemorphology
1 – This is the funnel area of the head. 2 – The arrow points to the right gill.
3 – The arrow points to the left funnel retractor muscle.
4 – The arrow points to the squid's rectum.
5 – The arrow points to one of the squid's branchial hearts. They receive deoxygenated blood from the precavae and the posterior vena cavae and pump it through the gills.
6 – The arrow points to one of the squid's precavae. These vessels containing the kidneys, receive deoxygenated blood from the head area via the anterior vena cava and direct it to the branchial hearts.
7 – The arrow points to one of the squid's posterior vena cavae. These vessels receive deoxygenated blood from the mantle area and direct it to the branchial hearts.
8 – The arrow points to the squid's caecum, a large chamber receiving masticated food from the stomach. Much of the digestion occurs here.
9 – The arrow points to the squid's single testis. Usually, it is partially covered by the caecum.

Morphology
1 – This is the funnel area of the head. 2 – This is the squid's rectum. It is terminated by two ear-like flaps.
3 – This is the left funnel retractor muscle.
4 – The arrow points to one of the squid's gills.
5 – The arrow points to the ink sac. This melanin-containing sac is dorsal to the intestine an empties into it.
6 – The arrow points to the squid's pair of nidamental glands. They secrete material that becomes the egg casings.
7 – The arrow points to the squid's left branchial heart. They receive blood from the vena cavae and pump it through the gills.
8 – This is the squid's ovary. It occupies much of this part of the mantle cavity and covers the caecum.

StellateGanglion
1 – This is the head area, seen laterally.
2 – This is the dorsal groove in the collar. The cartilaginous ridge in the head fits into it. The groove is supported internally by the pen.
3 – This is the collar.
4 – This is the stellate ganglion, a mass of cell bodies with giant motor axions that innervate the muscles of the mantle for rapid swimming.
5 – This is the squid's left gill. It has been injected with red latex.
6 – This is the left funnel retractor muscle.

Latin.mollis = soft)
This phylum is one of the largest marine groups with over 80 000 species. All comprise of a soft, unsegmented body, consisting of an anterior head, a dorsal visceral mass and a ventral foot.The body is more or less surrounded by a fleshy mantle (an outgrowth of the body wall) and nearly all species in the group secrete a lime shell that covers and protects the body. All, except the class Bivalvia, have a ribbon-like rasping tongue (radula - unique to this phylum) with small chitinous teeth that processes the food. Most mollusks are free living, but slow moving creatures, showing a close association with the substrate. Some attach to rocks or shells, others burrow, others float, octopuses and squids swim freely.
Characteristics:
1. Body usually short and partially or wholy enclosed by a fleshy outgrowth of the body wall called the mantle, which may be variously modified. Between the mantle and the visceral mass is a mantle cavity containing components of several systems (secondarily lost in a few groups).
2. A shell (if present) is secreted by the mantle and consists of one, two or eight parts. the head and the ventral muscular foot are closely allied (the foot being variously modified for burrowing, crawling, swimming, or food capture).
3. The digestive canals are complete and intricate with ciliary canals for the sorting of particles. The mouth with a rudula bearing traverse rows of minute chitinous teeth to rasp food , except in Bivalvia. The anus opening in the mantle cavity. A large digestive gland and often salivary glands are present.
4. The circulatory system is open, except in Cephalopoda and usually includes a dorsal heart with one or two atrias and one ventricle. This is situated in a pericardial cavity. An anterior aorta and other vessels and many blood spaces (hemocoels) exist in the tissues.
5. Respiration occurs via one to many uniquely structured ctenidia (gills) in the mantle cavity (secondarily lost in some), by the mantle cavity, or by the mantle.
6. Excretion by kidneys (nephridia), one or two or six pairs, or only a single one. They usually connect to the pericardial cavity and they exit in the mantle cavity. The coelom is reduced to the cavities of the nephridia, gonads and pericardium.
7. The nervous system is typically a circumesophageal nerve ring with multiple pairs of ganglia and two pairs of nerve cords (one pair innervating the foot and another the visceral mass). Many poses organs for smell, or touch, or taste. Eyespots or complex eyes present. A statocyst for equilibration present.
8. The sexes are usually seperate(some are monoecious, a few are protandric). Gonads add up to four, two or one, all with ducts. Fertilization occurs externally or internally. Most species are oviparous. Egg cleavage determinate, spiral, unequal and total (meroblastic in Cephalopoda). Trochophores and veliger larvae form, or a parasitic stage occurs(Unionidae), or the development is direct (Plumonata, Cephalopoda).
9. Unsegmented (except Monoplasophora). Symmetry bilateral or asymmetrical.

CITE:

Prepared by the BioG 101-104 Course Staff.Comments to Jon C. Glase: jcg6@cornell.eduAll contents © 2000 Cornell University. All rights reserved.Revised: April 5, 2000URL: http://biog-101-104.bio.cornell.edu/
http://library.thinkquest.org/26153/marine/mollusca.htm

Virtual Dissection - Starfish

2007-10-17T22:17:00.000-07:00

Echinoderms

The echinoderms include only marine animals -- starfishes, sea urchins, sea cucumbers, and sand dollars. The starfish will be studied as the representative for this group. Their unique feature is the water vascular system, which is used as a means of locomotion. They also have a carbonaceous endoskeleton, whose projecting spines give the phylum its name - "spiny skin" in Greek. The echinoderms seem the most unpromising of all as potential ancestors of the vertebrates. They are radially symmetrical, in contrast to vertebrates; they have no internal skeleton, no trace of any of the three major chordate characters of notochord, nerve cord, or gill slits, and they have many peculiar and complicated organs of their own. But the embryology sheds an unexpected gleam of light. The early embryo of the echinoderm is a tiny creature, which floats freely in the sea water. Unlike the adult, the larva is bilaterally symmetrical, suggesting that the radial symmetry of the starfish is a secondary affair, assumed when the ancestors of these forms look up a sedentary existence. Then, too, the type of development of certain of the body cavities is identical with that found in the embryos of some primitive vertebrates. It is believed that the bilateral larva developed types which retained the original symmetry, and gradually evolved into the chordates and, finally, the true vertebrates.

Circulatory - Coelomic fluid, circulated by ciliary action, performs many of the normal functions of a circulatory system.

Digestive - Starfishs feed on mollusks. When a starfish attacks a clam, it arches its body over the shell, and by the concerted action of the tube feet, forces the clam to open. Then it everts a portion of its stomach to digest the contents of the clam. The mouth of a starfish opens into a narrow esophagus, which in turn leads to an expanded stomach. The stomach has two portions: the saclike cardiac, which can be everted as described, and the narrower pyloric, which is connected to a short intestine. The anus opens on the aboral or upper side of the animal.

Exocrine - Each of the five arms contains a well-developed coelom, a pair of large digestive glands that secrete powerful enzymes into the pyloric portion of the stomach, and gonads.

Excretory - Starfish has no excretory organs.

Immune - Sea urchins are long lived, normally healthy animals that display remarkable abilities to heal wounds and combat major infections. From an external point of view, their immune systems obviously work very well. Thus, their cellular defense systems are extremely sensitive, and they respond rapidly to minor perturbations, all without any specific adaptive capabilities. These systems probably function through the transduction of signals conveying information on injury and infection, just as do the equivalent systems that underlie and back up the human immune systems, and that provide the initial series of defenses against pathogenic invasions.

Musculo-skeletal - The water vascular system is purely for locomotion. Water enters this system through a structure on the aboral side called the sieve plate, or madreporite. From there, it passes through a short canal called the stone canal, to a ring canal, which surrounds the mouth. From the ring canal, five radial canals extend into the arms. From the radial canals, many lateral canals extend into the tube feet. One lateral canal goes to each tube foot, where it ends in the ampulla. When the ampulla contracts, the water is forced into the tube foot, expanding it and giving it suction. By alternating the expansion and the contraction of the tube feet, the starfish moves along slowly. Typically, echinoderms have an endoskeleton (internal skeleton) consisting of hard calcite ossicles embedded in the body wall and often bearing protruding spines or tubercles.

Nervous and Sensory - The nervous system consists of a central nerve ring that supplies radial nerves to each arm. A light-sensitive eyespot is at the tip of each arm.

Reproductive - The starfish usually becomes sexually mature at about 12-14 months. Mating mainly takes place between May and June (water temp. about 8 °C) when the whole population are at the same depth and like an epidemic. The lifecycle of most starfishes starts by shedding their eggs and sperm freely into the water, so fertilization is externally. The very small chance of fertilization is compensated by the enormous amounts of eggs and sperm cells. A female starfish sheds in two hours several millions of eggs into the water, with a mean diameter of 0.16-0.19 mm . After fertilization, a hollow ball develops, called the blastula. The cells of the blastula possess cilia on the outside for swimming. After one day a deep groove develops, leading to the gastrula. The gastrula's of all types of echinoderms are very similar. But then differentiation starts. The common starfish develops a so-called bipinnaria larva, with ciliated bands running about the periphery. After several weeks the bipinnaria larva takes on a more elaborate form, with longer projecting arms and after some more weeks, a brachiolaria larva is formed. The larvae have their own gut, with inside cilia to inhale and transport food particles. They feed themselves with diatoms and other organisms in the plankton. The stomach is large and round and situated at the backside. After this phase a large part of the larva degenerates and at the rear side a rudimentary formed juvenile starfish develops. The organs of the young starfish are formed anew.

Respiratory - There are skin gills, which project from the coelomic cavity, serve the function of respiratory exchange.

CITES:

http://images.google.com/imgres?imgurl=http://universe-review.ca/I10-82-starfish.jpg&imgrefurl=http://universe-review.ca/R10-33-anatomy.htm&h=423&w=650&sz=61&hl=en&start=1&tbnid=0_dbmbiE_wzM5M:&tbnh=89&tbnw=137&prev=/images%3Fq%3Dstarfish%2Banatomy%26gbv%3D2%26svnum%3D10%26hl%3Den%26sa%3DX

Virtual Dissection - Clam

2007-10-17T21:30:00.000-07:00

Overview images of clam, left mantle removed

1 – This is the clam's foot, a muscular organ used for digging. Two retractor muscles withdraw the foot into the shell.
2 – This is the anterior adductor muscle, a major muscle for closing the valves.
3 – This is the posterior adductor muscle, a major muscle for closing the valves.
4 – This is the visceral mass, a thickened region extending from the foot dorsally to the pericardial cavity and bordered by the mouth and siphons. The visceral mass contains the organs of digestion and reproduction.
5 – These are the siphons. The upper arrow points to the excurrent siphon, the lower arrow, the incurrent siphon.
6 – These are the gills. Two pairs of gills are found on each side of the clam.
7– These are the labial palpi. The palpi form the boundry of the mouth on their anterior end. They are covered with heavily ciliated cells and direct food toward the mouth.
8 – The arrow shows the ventral margin of the right mantle. Note that the right mantle joins the reminants of the left mantle to form the incurrent and excurrent siphons.
9 – The arrow points to the pericardial cavity, covered with a thin, dark membrane.

Overview image of clam, left valve removed

1 – This is the clam's left mantle. The mantle secretes the shell and is attached to it along the pallial line seen on the inner surface of an empty valve. Note: the left mantle was detached from the left valve when it was removed. The black arrows show the border of the left mantle.
2 – This is the anterior adductor muscle, a major muscle for closing the valves.
3 – This is the posterior adductor muscle, a major muscle for closing the valves.
4 – This is the pericardial cavity, a region covered with a thin, dark membrane that contains the heart, kidney, etc.
5 – This is the margin of the right mantle. The right and left mantles join together to form the incurrent and excurrent siphons.
6 – This is location of the incurrent and excurrent siphons.

Image of inner surface of valve

1 – This is the inner surface of the clam's left valve. In the dissection you performed, this valve was removed for you.
2 – This is the posterior adductor muscle, a major muscle for closing the valves. The sea food we call scallops are the adductor muscles of the bivalve known as the pecten.
3 – This is the anterior adductor muscle, a major muscle for closing the valves. To open a clam, a thin knife is slid between the valves and the two adductor muscles are cut.
4 – This is the hinge area of the shell. A hinge ligament holds the valves together. Interlocking teeth in this area prevent the valves from side slipping when closed.
5 – Small teeth border the margin of each valve. These teeth prevent the valves from sliding laterally when the shell is closed.
6 – The arrow points to the posterior shell region where the incurrent and excurrent siphons are positioned.
7 – This structure indicated is the umbo of the shell. This is the oldest part of the shell.
8 – This narrow line (called the pallial line) on the inner surface of the shell connecting the two adductor muscles is the region where the mantle was attached to the shell. An indentation in this line marks the location of the two siphons.

Image of intact clam

1 – This is the clam's left valve. In the dissection you performed, this valve was removed for you.
2 – This indicates the anterior or head end of the clam.
3 – This indicates the posterior or tail end of the clam.
4 – This indicates the dorsal or upper surface of the clam.
5 – This indicates the ventral or lower surface of the clam.
6 – This structure indicated is the umbo of the shell. This is the oldest part of the shell.
7 – This faint line indicated on the surface of the shell is a growth ring. Notice how all growth rings emanate from the umbo.

Clam
(Venus mercenaria)
Kingdom: Animalia
Phylum: Mollusca
Class: Pelecypoda
Order: Eulamellibranchia
Family: Veneridae
Genus: Venus
Species: mercenaria

Adductor muscle(s)
Removal of the mantle shows the underlying soft body parts, a prominent feature of which are the adductor muscles in dimyarian species (clams and mussels) or the single muscle in monomyarian species (oysters and scallops). In clams and mussels the two adductor muscles are located near the anterior and posterior margins of the shell valves. The large, single muscle is centrally located in oysters and scallops. The muscle(s) close the valves and act in opposition to the ligament and resilium, which spring the valves open when the muscles relax. In monomyarian species the divisions of the adductor muscle are clearly seen. The large, anterior (striped) portion of the muscle is termed the "quick muscle" and contracts to close the valves shut; the smaller, smooth part, known as the "catch muscle," holds the valves in position when they have been closed or partially closed. Some species that live buried in the substrate (e.g. clams) require external pressure to help keep the valves closed since the muscles weaken and the valves open if clams are kept out of a substrate in a tank.
Gills
The prominent gills or ctenidia are a major characteristic of lamellibranchs. They are large leaf-like organs that are used partly for respiration and partly for filtering food from the water. Two pairs of gills are located on each side of the body. At the anterior end, two pairs of flaps, termed labial palps, surround the mouth and direct food into the mouth.
Foot
At the base of the visceral mass is the foot. In species such as clams it is a well developed organ that is used to burrow into the substrate and anchor the animal in position. In scallops and mussels it is much reduced and may have little function in adults but in the larval and juvenile stages it is important and is used for locomotion. In oysters it is vestigial. Mid-way along the foot is the opening from the byssal gland through which the animal secretes a thread-like, elastic substance called "byssus" by which it can attach itself to a substrate. This is important in species such as mussels and some scallops enabling the animal to anchor itself in position.
Digestive system
The large gills filter food from the water and direct it to the labial palps, which surround the mouth. Food is sorted and passed into the mouth. Bivalves have the ability to select food filtered from the water. Boluses of food, bound with mucous, that are passed to the mouth are sometimes rejected by the palps and discarded from the animal as what is termed "pseudofaeces". A short oesophagus leads from the mouth to the stomach, which is a hollow, chambered sac with several openings. The stomach is completely surrounded by the digestive diverticulum (gland), a dark mass of tissue that is frequently called the "liver". An opening from the stomach leads to the much-curled intestine that extends into the foot in clams and into the gonad in scallops, ending in the rectum and eventually the anus. Another opening from the stomach leads to a closed, sac-like tube containing the crystalline style. The style is a clear, gelatinous rod that can be up to 8 cm in length in some species. It is round at one end and pointed at the other. The round end impinges on the gastric shield in the stomach. It is believed it assists in mixing food in the stomach and releases enzymes that assist in digestion. The style is composed of layers of mucoproteins, which release digestive enzymes to convert starch into digestible sugars. If bivalves are held out of water for a few hours the crystalline style becomes much reduced and may disappear but it is reconstituted quickly when the animal is replaced in water.
Circulatory system
Bivalves have a simple circulatory system, which is rather difficult to trace. The heart lies in a transparent sac, the pericardium, close to the adductor muscle in monomyarian species. It consists of two irregular shaped auricles and a ventricle. Anterior and posterior aorta lead from the ventricle and carry blood to all parts of the body. The venous system is a vague series of thin-walled sinuses through which blood returns to the heart.
Nervous system
The nervous system is difficult to observe without special preparation. Essentially it consists of three pairs of ganglia with connectives (cerebral, pedal and visceral ganglia).
Urogenital system
Sexes of bivalves can be separate (dioecious) or hermaphroditic (monoecious). The gonad may be a conspicuous, well defined organ as in scallops or occupy a major portion of the visceral mass as in clams. The gonad is generally only evident during the breeding season in oysters when it may form up to 50% of the body volume. In some species such as scallops, the sexes can be readily distinguished by eye when the gonad is full since the male gonad is white in colour and the female is red, even in hermaphroditic species. Colour of the full gonad may distinguish the sexes in some species such as mussels. In other species, microscopic examination of the gonad is required to determine the sex of the animal. A small degree of hermaphrodism may occur in dioecious species.
Protandry and sex reversal may occur in bivalves. In some species there is a preponderance of males in smaller animals indicating that either males develop sexually before females or that some animals develop as males first and then change to females as they become larger. In some species, e.g. the European flat oyster, Ostrea edulis, the animal may spawn originally as a male in a season, refill the gonad with eggs and spawn a second time during the season as a female.
The renal system is difficult to observe in some bivalves but is evident in such species as scallops where the two kidneys are two small, brown, sac-like bodies that lie flattened against the anterior part of the adductor muscle. The kidneys empty through large slits into the mantle chamber. In scallops, eggs and sperm from the gonads are extruded through ducts into the lumen of the kidney and then into the mantle chamber.

CITES:
Prepared by the BioG 101-104 Course Staff.Comments to Jon C. Glase: jcg6@cornell.eduAll contents © 2000 Cornell University. All rights reserved.Revised: April 5, 2000URL: http://biog-101-104.bio.cornell.edu/
http://www.fao.org/docrep/007/y5720e/y5720e07.htm

DIATOM

2007-10-15T22:15:00.000-07:00

PARTS AND FUNCTION

Frustule (glassy shell) – consists of two tightly fitting halves often resembling a flat, round, or elongated box. Also has intricate perforations and ornaments such as spines or ribs. The Frustule allows light to pass through so that the conspicuous golden-brown chloroplasts can capture light energy for photosynthesis.

Nucleus

Chloroplast – are the most noticeable internal component of almost all diatoms, giving the diatom its color and photosynthetic capabilities. Diatom chloroplasts are usually yellowish-brown in color, ranging between yellowish-green and dark brown. This coloration is due to the presence of photosynthetic pigments such as chlorophyll, beta carotene, and fucoxanthin. The pigment chlorophyll is also a key component of terrestrial plants. Without this pigment, neither plants nor diatoms grow very well.

Mitochondrion

Oil Droplet

Reproduction – Under the right conditions, diatoms can reproduce very rapidly and a population of a small species can double each day. Diatoms normally reproduce by binary fission, where one ‘mother cell’ splits into two daughter cells. The two halves of the mother frustule become the ‘lids’ for the daughter frustules- the ‘box’ parts are made inside, as the daughters separate. One daughter cell will therefore be the same size as the parent, and the other will be slightly smaller. Over time, a lineage of diatoms will get smaller and smaller, although a few species avoid this problem by having stretchable frustules. When cells get too small, they discard their old frustules and build new, much larger ones. This process can be connected to sex. In many centrics, some individuals will break up into many small sperm-like cells. These ‘fertilise’ other diatoms, which then produce new, large frustules. In pennates, ‘sex’ involves two adult cells lining up alongside each other, dividing and then swapping one daughter cell each. The new pairs of daughter cells fuse, giving two cells that are each half of each ‘parent’. They then produces new, large frustules and glide away.

NAME OF ORGANISM
Scientific Classification
Domain: Eukaryota
Kingdom: Chromalveolata
Phylum: Heterokontophyta
Class: Bacillariophyceae
Order: Centrales and Pennales

HABITAT

Almost all living diatoms require sunlight to survive and photosynthesize, limiting them to the uppermost 200 meters of the water column. This sunlit region of the water column is referred to as the photic zone. Since the entire surface of the ocean is exposed to sunlight at least part of the year, diatoms live practically everywhere at the sea surface. Diatoms are classified into two categories according to their lifestyle: planktonic or benthic. Since all diatoms are photosynthetic, both planktonic and benthic diatoms are restricted to living within the photic zone. Centric diatoms are mostly planktonic, floating near the sea surface, while pennate diatoms are mostly benthic, living on the seafloor, or attached to floating objects.

FOOD SOURCE

DESCRIPTION OF LIFE CYCLE

HOW DOES IT MOVE

UNIQUE CHARACTERISTICS

ROLE IN THE ECOSYSTEM
Like many micro-organisms, diatoms can bloom when conditions of nutrients, light and temperature are ideal. While diatom blooms are a major source of energy for the ocean, which ultimately supports the large predators such as fish and marine mammals and birds, severe blooms can be harmful. One diatom can kill farmed fish because its barbed spines can wound gills. Chemicals present in diatoms can build up in the bodies of animals that eat them and if concentrated enough, can affect people that eat the animals. In Australia, diatom blooms have been responsible for making shellfish unpleasant to taste and unsaleable for long periods of time. One diatom is responsible for Amnesic Shellfish Poisoning, a potentially fatal illness whose symptoms include memory loss. Worldwide outbreaks to date have been very rare, however there is concern that human activities are increasing the frequency of many sorts of micro-organism blooms (see silicoflagellates).

CITES: http://earthguide.ucsd.edu/diatom/d10.html; http://www.reef.edu.au/asp_pages/secb.asp?FormNo=7; http://images.google.com/images?hl=en&q=diatom&gbr=2

September 18, 2007 Presentations by Dr. Houk & Mr. Villagomez

2007-10-10T21:44:00.001-07:00

WALK IT, DON'T DRIVE IT!

During the presentation of the "Walk It, Don't Drive It" campaign by Dr. Houk and Mr. Villagomez, I learned the significance of keeping automobiles away from the sand of our beaches. The important reasons why automobiles should never be driven on our sandy beaches are summarized below:

D = Drips - oil that drips end up in our ocean and is deadly to our marine organisms.

R = Ruts - turtles lay their eggs on the sand and we should do everything humanly possible to protect them.

I = Illegal - It is illegal to drive on the beach of the CNMI! Everyone must follow the Law!

VE = Vegetation - vegetation on beaches are essential because they keep the sand from running off.

We viewed first hand that police officers were not following the Law while patrolling on the beaches. According to Dr. Houk and Mr. Villagomez, they have done a presentation with the DPS so hopefully their message came across.

I for one will admit that I have driven on the beaches of our island but after this presentation I definitely have a better understanding of why I should not be driving on our beaches. Good Job! Dr. Houk & Mr. Angelo. Rest assured your message will be passed on to many more that are not educated of the importance of keeping automobiles away from our beaches.

Watershed Ecology

2007-10-10T21:44:00.000-07:00

CITE: Picture obtained from US EPA http://www.epa.gov/watertrain/ecology/index.html

Chapter 19 - Level 2 Quiz

2007-10-10T21:27:00.005-07:00

Chapter 6 - Level 2 Quiz

2007-10-10T21:27:00.004-07:00

Chapter 5 - Level 2 Quiz

2007-10-10T21:27:00.003-07:00

Chapter 4 - Level 2 Quiz

2007-10-10T21:27:00.002-07:00

Chapter 3 - Level 2 Quiz

2007-10-10T21:27:00.001-07:00

Chapter 1 - Level 2 Quiz

2007-10-10T21:27:00.000-07:00

SEE FORUMS (Chapter 18, Page 422)

2007-09-26T05:17:00.000-07:00

Critical Thinking - Question 3

Tourism and its effects (for example, pollution from hotels and the impact of boats and tourists on fragile habitats) often clash with conservation efforts. Sometimes, however, tourism can help. The economic impact of banning the hunting of harp seals in eastern Canada has been compensated for, in part, by the influx of tourists who now come to see the seals. Can you think of other examples? What recommendations can you make to minimize the impact of tourism on unspoiled marine environments?

An example that I believe will work is to EDUCATE! Educate by handing out brochures, in languages that the tourists use, explaining the effects on our marine environment while having their fun in our waters. Businesses have brochures readily available to promote their sales on water activities regardless of the damages it causes everyone. People like us who care together with Marine Biologists that are on island and Coastal Resources Management staff should come up with our own educational brochures to be made readily available to tourists.

The recommendation that I will make to minimize the impact of tourism on unspoiled marine environments is to INFORM! Inform tourists the importance of our marine organisms in our daily lives compared to their water sport activities for just a few hours of fun. Suggest to tourists that if being in our ocean to view the many different species of organisms is their passion, then perhaps they can contribute in many ways by becoming a Marine Biologist or by volunteering.

Algae Cell - 09/25/07

2007-09-25T00:40:00.000-07:00

Eukaryote (Algae)
Eukaryote - an organism that consists of one or more eukaryotic cells.
Eukaryote Cell - a cell that contains a nucleus and other organelles.

The parts of an algae from top to bottom and their function is as follows:
Cell Wall - protects the Cytoplasmic membrane.

Cytoplasmic Membrane - the very thin, highly flexible, but structurally weak membrane that lies under the wall and surrounds the interior of the cell.

Cytoplasm - the cell interior which consists of a solution of salts, sugars, amino acids, vitamins, and a wide variety of other soluble materials in water. Since the Cytoplasm has a higher solute concentration than the water surrounding the cell, osmosis causes water to pass from outside the cell through the relatively permeable cell wall, continue through the cytoplasmic membrane, and dilute the cytoplasm. This builds up pressure within the cell until it equalizes to the effective osmotic pressure and, if not for the rigidity of the cell wall, the cell would burst. Other chemical compounds necessary for the life of the cell are selectively passed through this membrane and waste products are evacuated through it.

Nucleus - contains most of the genetic material of the cell, and the DNA (deoxyribonucleic acid) molecules exist as linear strands. The DNA is condensed into obvious chromosomes only at the time of nuclear division (mitosis) in most algae; however, the nuclear DNA of the classes Dinophyceae and Euglenophyceae is always condensed.

Nuclear Membrane - has specialized nuclear pores that regulate the movement of molecules into and out of the nucleus.

Nucleolus - within the nucleus are found chromatin and a structure called the nucleolus. Chromatin is DNA in its active form. It consists of DNA looped around histone proteins. The nucleolus is a knot of chromatin. It is the nucleolus that manufactures ribosomes

Mitochondrion - is the site where food molecules are broken down and carbon dioxide, water, and chemical bond energy are released, a process called cellular respiration. Special organelles where respiration takes place. Mitochondria are the cell's power plants, breaking down organic molecules to provide energy.

Ribosomes - serves as the “workbench” during protein synthesis. It provides the site where genetic information, as messenger RNA, is translated into proteins. The ribosome carefully interprets the genetic code of the DNA so that the protein is made exactly to the genetic specifications.

Function:
Chiefly aquatic, eucaryotic one-celled or multicellular plants without true stems, roots and leaves, that are typically autotrophic, photosynthetic, and contain chlorophyll. Algae are not typically found in groundwater. They also may be attached to structures, rocks or other submerged surfaces. They are food for fish and small aquatic animals. Excess algal growths can impart tastes and odors to potable water. Algae produce oxygen during sunlight hours and use oxygen during the night hours.

2 Examples of organisms with algae cell:

1. Ulva (Sea Lettuce) - green alga
2. Padina - brown alga

Questions:

1. Where does respiration take place in an algae cell?
2. What part of the algae cell manufactures ribosomes?
3. What does algae produce during sunlight hours?

SEE FORUMS (Observing Your World)

2007-09-20T21:06:00.000-07:00

Science is the process of trying to make sense of the world around us. Every culture has its own way of making sense of how the world works. Modern science follows a tradition of asking questions, forming hypothesese, testing the hypothesese through experimentation and recording observations. These observations are compared against the observations of others to see if the results are varifiable or reliable. Most of what we accept as factual in science was ascertained by this process. There are limitations to this world view and there are other ways of coming at the same information or at the very least recognizing patterns in the environment etc. without necessarily knowing why.What are your cultural ways of understanding the world? How do you do science? What conflicts have you faced or contradictions?

One of the most touching cultural practice for me as a Chamorro that began since I was a young girl is what we do for our departed loved one. Because we strongly believe that prayers are very powerful, we pray for our dead so they can be allowed into Heaven and be by our Lord's side. Our belief is that if a spirit of a loved one lingers in Purgatory, through prayers from family members and friends, that spirit makes its way into heaven. It is customary for us Chamorro's to pray the rosary for 18 straight days . The first 9 days of rosary is open to the public and the remaining 9 days are only for immediate family members. Through experience of having lost loved ones, I believe that as we gather together to pray the rosary, we not only help our beloved ones reach heaven but also help each other cope through the difficult times. This in itself explains why I am so touched by this cultural practice of ours.

Our cultural ways of understanding the world I would have to say is through "respect." Respect is strongly practiced in our culture. Respect for the land! Respect for the animals! Respect for the plants! Respect for the dead! Respect for the elders! Respect for the visitors! Respect for the people who do not believe in God! Basically, respect our entire surroundings because it is our way of life.

My way of doing science is through observations, documentations and experimentations.

One conflict that I have faced is our custom of having to provide food for everyone during the 19 days of rosary. Not only is this custom a burden for the surviving spouse, it really is not realistic.

Paupau Beach - 9/15/07

2007-09-16T15:33:00.000-07:00

What was supposed to be a snorkeling adventure at Paupau Beach for me turned out to be an obeservation of the watershed pipes and the effects it would have on our marine environment. This is only because I forgot to bring my contact lenses. Lesson learned for me, "carry contact lenses at all times!"

It was unfortunate that I did not witness the amount of water that flows out of the huge pipes built on the shore of Paupau Beach. Although I did not see any action of water flow at the time, I could imagine just form the size of those pipes, that tons of water drains out from there and straight into our ocean. The water that has been flowing out of the pipes for many months now left a trail about 6 feet wide that leads down the beach. I followed the trail down and found branches as well as coconuts soaked and so old they had algae growing on them. Algae also grew on the rocks that were laying around on the trail.

SEE FORUMS (Chapter 14, Page 323)

2007-09-15T23:21:00.002-07:00

Critical Thinking - Question 1

Pictures of Atoll in the Hawaiian Islands and Atoll in the Pacific Ocean

What factors might account for the fact that the vast majority of atolls occur in the Indian and Pacific oceans and that atolls are rare in the Atlantic?

Temperature is the factor of why vast majority of atolls occur in the Indian and Pacific Oceans and are rare in the Atlantic. Reef corals require warm water. Figure 14.11 (Marine Biology sixth edition - Castro/Huber) showed that there are more warm surface currents in the Indian and Pacific ocean than in the Atlantic Ocean.

Student Notes Only:

Atoll - A coral reef that develops as a ring around a central lagoon.

CITE: Pictures obtained from http://images.google.com/images?gbv=2&svnum=10&hl=en&q

SEE FORUMS (Chapter 7, Page 152)

2007-09-15T20:43:00.000-07:00

Critical Thinking - Question 3

A new class of echinoderms, the sea daisies or concentricycloids, was discovered in 1986. They are deep-water animals living on sunken wood. They are flat and round, looking very much like a small sea star without arms. They also lack a gut. Without ever having seen them, why do you think they were classified as echinoderms, not as members of a new phylum? Any hypotheses as to how they feed or move around?

I think the sea daisies were classified as echinoderms and not as members of a new phylum simply because they look very much like a small sea star without arms. Having this similarity definitely would mean that they are related somehow.

Hypotheses: Sea daisies feed and move around using the central part of their body.

STUDENT NOTES ONLY:
Echinoderms - Invertebrates (no back bone) with five-way radial symmetry (the regular arrangement of similar body parts around a central axis) and a water vascular system (a network of water-filled canals in echinoderms used on locomotion and food-gathering). Examples are sea cucumbers, starfishes, sea urchins, etc.

Phylum - The taxon (a group of organisms that share a common ancestry) that represents a main division of a kingdom

Hypotheses - A statement that might be true.

CITE: Picture obtained from http://images.google.com/images?gbv=2&svnum=10&hl=en&q

The Shape of Life - 09/08/07

2007-09-10T08:40:00.000-07:00

Episode 1 – Organisms (Sponges)

1. What organism is thought to be the first multi-cellular animal? Ancient Sponge

2. How is it the same (3 ex) and diff (3 ex) from animals today?

Animals Today
- move
- feed themselves
- reproduce and care for their young
- engage in fear territorial boundaries

Sponges
- mysterious (have lots of secrets)
- no definite shape
- 9,000 different species
- live both in cold and warm places
- vibrant animal
- cells are unique in the animal kingdom
- cells have a unique way of working together
- does not have a heart, nervous system or blood
- perform many responsibilities
- continuously re-invent themselves
- no other plant or animal can resurrect themselves the way sponges do

3. How do scientists know it’s an animal? Through a process - Gene Sequencing

4. What evidence do scientists have to prove that other animals (multi-cellular) evolved from this organism? Through DNA testing which proved that all animals evolved from the same blue print

5. What more do you want to know? How many different species of sponges live in our ocean, the Pacific Ocean?

Additional Information:

Way of feeding of a Sponge: they are a living filtering machine sucking water and filtering out particals. 1 ton of water = 1 ounce of food

Sex life of a Sponge: their sex life is affected through pumping. Pumping = feeding and reprodcution.

I enjoyed this movie very much because it was very detailed and understandable. Most especially learning that we evolved from a sponge, "DYNAMIC!"

CITE: pictures obtained from http://images.google.com/images?gbv=2&svnum=10&hl=en&q

Tide Chart - 08/28/07

2007-09-10T07:34:00.000-07:00

Mount Laulau - 09/08/07

2007-09-10T07:30:00.000-07:00

TOUCHING:

It is a beautiful thing knowing that there are people out there aside from our local people that show a great deal of love and caring for our islands. Thank you Angelo and Bree. Your dedication and devotion are vary much appreciated. I am very interested in doing volunteer work to beautify CNMI. I will be checking your blogs for scheduled dates and you will definitely see me around. I will also bring family and friends to lend a helping hand.

The hike to Mount Laulau was a bit difficult for me but very interesting. Our class was accompanied by Angelo.

Angelo explained that the local ways of clearing land is by burning the trees which is not good. He went on and explained that when the trees are burned, not only does it spread further but the fire also burns the soil. When soil is burned, it becomes very dry so when it rains or we have a typhoon, there is a runoff of burned soil from Mount Laulau into our ocean.

I learned that the disadvantage of the soil being burned is that it becomes acidic disallowing plants and trees to grow. When there are no plants and trees on the hill, the soil becomes loose allowing runoffs to happen on rainy or typhoon days. The advantage of having plant and trees planted on the hill is to hold the soil in place and avoid major runoffs. Angelo showed us areas where ferns grew on the hill and he said that ferns grow well on acidic soil but plants and trees does not.

Angelo also explained that farmers near the hill uses fertilizers and pesticides and these also gets washed down into our ocean by rain or typhoon. In addition to farmers is the golf course in which they use chemicals for the growth of their grass and although a beautiful sight to see, the chemicals are deadly for our marine animals.

Economic View:

Because Laulau is one of the best diving spots for tourists, it is important to keep Laulau beach clean so marine life will be present for many years to come. An estimate of divers per day at Laulau is 100 with a diving cost of between $75 to $100 making about $1,000 daily.

The hike was a learning and an enjoyable experience for me and I hope we will do more before our semester is over. I definitely will inform my family that they should not burn trees as a way of clearing their land.

San Antonio Beach - 08/25/07

2007-09-08T20:01:00.000-07:00

Our very first Lab was at San Antonio Beach where we would collect marine animals and put them in our class aquariums for extra points. I always strive for the extra points for a better grade. The snorkeling was fun but the water was nasty.

Below are pictures and information on the marine animals that were caught and also some of my observations of the San Antonio Beach.

CHECK IT OUT!

1. Banded pepefish, Corythoichthys intestinalis, 10 cm [Family Syngnathidae - Pipefishes & Seahorses]

2. Synapta maculata (Synaptidae), 140 cm [Holothurians - Family Synaptidae, etc.]
Charmaine, Justo and myself found one just like this one but it was returned back into the ocean because someone had already collected one.

3. Diadema savignyi (Dia dematidae), 20 cm [Sea Urchins]

4. Frog shell, Bursa rubeta (Bursidae) [Murex Shells, etc.]

5. Shrimp

6. Fishes

7. Black Boxfish or Puffer (I thought this fish was really cute)

8. Black Sea Cucumber

My observation of San Antonio Beach:

- Lots of Sea Weeds

- Lots of algae

- Lots of Black Sea Cucumbers

- Many different types of small fish

- fish travel in small groups apart from each group

- parrot fish (Bullethead parrotfish, Scarus sordidus, 30 cm - Parrotfishes - Family Scaridae)

- striped fish (Striped surgeon fish, Acanthurus lineatus, 35 cm - Surgeonfishes - Family Acanthuridae)

- butterfly fish (Moorish idol Zanclus cornutus, (Zanclidae) 22 cm - Surgeonfishes - Family Acanthuridae, etc.

- Lots of small holes in the sand that the fish use to hide (home)

- Fish hides underneath rocks as well as in between (home)

- Fish are mostly present where the wreckage remain at the very bottom (home)

CITE: pictures obtained from http://images.google.com/images?gbv=2&svnum=10&hl=en&q

Obyan Beach - 09/03/07

2007-09-04T06:19:00.000-07:00

While snorkeling at Obyan Beach, I saw the following fish. These fish were mostly small in size and they travel in a small group. I love eating fish and while observing these fish I wondered about fishermen and how much more different species of fish they see all the time. Then I began to realize why people love diving. I never dove but hopefully one day I will learn how and at the same time become a certified diver.

ENJOY THE VIEW!

1. Parrot Fish – Bleeker’s parrotfish, Scarus bleekeri, 35 cm (W. Pacific) [page 327 – Field Guide]

2. Tataga – Bluespine unicornfish, Naso unicornis, 40 cm [page 337 – Field Guide]

3. Hangun – Orangespine unicornfish, Naso lituratus, 35 cm [page 337 – Field Guide]

4. Striped Fish W/Sharp Blade Near Tail – Sohal surgeonfish, Acanthurus sohal, 30 cm (Red Sea) [page 337 – Field Guide]

5. Tiny Gray Fish W/Black Vertical Stripes – Convict surgeonfish, Acanthurus triostegus, 25 cm [page 337 – Field Guide]

6. Butterfly Fish – Moorish idol, Zanclus cornutus, (Zanclidae) 22 cm [page 339 – Field Guide]
(SAME PICTURE AS THE SAN ANTONIO BEACH PUBLISHED POST)

7. Pipefish – Banded pipefish, Corythoichthys intestinalis, 10 cm [page 267 – Field Guide]
(SAME PICTURE AS THE SAN ANTONIO BEACH PUBLISHED POST)

8. Gadao – Dwarf-spotted grouper, Epinephelus merra, 18 cm [page 275 – Field Guide]

9. Baby Yellow/Black Striped Fish – Gold-lined sea bream, Gnathodentex aurolineatus, 25 cm [page 288 – Field Guide]

10. I’I or E’E/Tarakitu – Thicklip trevally, Carangoides orthogrammus, 40 cm [page 283 – Field Guide]

Below is a sea cucumber that Charmaine, Marge and Justo collected at Obyan Beach. While working on my assignment on sea daisies, I stumbled into this picture and amazingly it looks exactly as disgusting as the sea cucumber that the three caught. Disgusting but very interesting!

Sea cucumber - The Sea cucumber, like the Brittle Star, belongs to a group of animals called the Echinoderms. Most are scavengers - some sift through the bottom sediments (like sand or mud); others trap their food by waving tentacles around their mouth in the water. Many types of sea cucumber will "throw up" many of their internal organs when attacked. These organs can regrow if they survive the attack.

CITE: pictures obtained from http://images.google.com/images?gbv=2&svnum=10&hl=en&sa=x&oi=spell&resnum=o&ct=result&cd=l&q

Interactive Experiments - 08/30/07

2007-08-30T00:25:00.000-07:00

Sour Foods

Question: What atoms are in sour foods?

Hypothesis: High concentration of loose hydrogen atoms are found in the most sour foods.

Supplies: 5 Cups, 5 Food Bottles, 5 Blank Labels, 1 Dye Bottle, Microscope, Marker & Food (Lemon Juice, Vinegar, Orange Juice, Milk and Water)

Steps: 1. Label each cup by clicking each blank label once.

2. Click on food bottle 1 and add five drops of food by clicking on cup 1 five times.

3. Put food bottle 1 back by clicking where you picked it up.

4. Repeat Steps 2 and 3 for food bottles 2, 3, 4 and 5.

5. Click on dye bottle and add one drop to each cup by clicking once.

6. Put dye bottle back by clicking where you picked it up.

7. Click continue to view chart for explanation of each dye color.

8. Drag the cups to order them from high concentration to a low concentration of loose atoms.

9. Click continue 2x, then click on each cup to find out what each food is, from most sour to least sour as follows:

a. Lemon Juice

b. Vinegar

c. Orange Juice; Apple

d. Milk; Banana

e. Water

10. Click continue to view pictures with information on sour foods.

Results: I learned that sour foods contain high concentration of loose hydrogen atoms. Therefore, food with high concentration of loose hydrogen atoms are the most sour like lemon juices and vinegar while food with a low concentration of loose hydrogen atoms are the least sour like milk and water.

Explanation:

Answer these questions:
1. What are acids and bases? Acid is a chemical that can react with a base to form a salt. Base is a chemical compound that unites with an acid to form a salt.

Student Notes Only: Salt - A substance that consists of ions that have opposite electrical charges.

2. What is a molecule? Molecule is a combination of two or more atoms.

3. Why is pH important in the ocean? For control (balance).

Holes in Bread

Question: What molecules make the holes in bread?

Student Notes Only: Molecules - are tiny particles that make up everything around us.

Hypothesis: Sugar molecules make the holes in bread.

Supplies: Yeast, Measuring Spoon, Cup, Tube, Sugar, Water Bottle, Warm Water, Stick, Timer, Flashlight & Microscope

Steps: 1. Use spoon and take 3 scoops of yeast from the cup and pour into the tube.

2. Use spoon and take 3 scoops of sugar from the cup and pour into the tube.

3. Pick up the warm water bottle and add 8 drops of water into the tube, then return the warm water bottle back to its place.

4. Use the stick by clicking on it and moving it to the left and to the right to stir the yeast and sugar into the water until the water is the same color as the yeast.

5. Wait a few minutes for the reaction in the tube to take place, then continue.

6. Shine the flashlight on the side of the tube by clicking its power switch.

7. Watch the tiny bubbles streaming up the side of the tube.

8. Press continue to view the explanation on what is going on in the tube.

9. Press continue to view the answer to what molecules make the holes in bread.

Results: From the holes in bread experiment, I learned that the chemical reaction of yeast and sugar combined will form new molecules, carbon dioxide gas molecules and alcohol molecules. The carbon dioxide gas molecules then makes the tiny bubbles. Therefore, to answer the question, "What molecules make the holes in bread?." My answer would be the carbon dioxide gas molecules.

Explanation:

Answer the question:

1. What gas causes the bubble? The carbon dioxide gas molecules make tiny bubbles.

2. How was the gas produced? Because yeast is a living thing that feeds on the sugar molecules, when combined together, it breaks the sugar molecules apart into new molecules forming the carbon dioxide gas molecules and alcohol molecules.

3. How does CO2 get in the ocean? The CO2 throughout the earth is constantly in flux. CO2 isn't trapped in the atmosphere or in the land for any length of time, as it becomes absorbed largely into the ocean (see Carbon Cycle for detailed explanation).

CITE: pictures obtained from http://images.google.com/images?gbv=2&svnum=10$hl=en&q

Tides - 08/28/2007

2007-08-29T13:56:00.000-07:00

a. What is tidal range? Tidal range is the difference in water level between successive high and low tides.

b. What causes high and low tides? High and low tides are caused by a combination of the gravity of the sun and moon and the centrifugal force that results from the rotation of the earth, moon, and sun.

Student Notes Only: Tides – The periodic, rhythmic rise and fall of the sea surface.

c. What causes Spring and Neap tides? Spring tides are caused when the sun and moon are in line with each other and their effects add together. Neap tides are caused when the sun and moon are at right angles and their effects partially cancel each other.

Student Notes Only: Spring Tides – The tides with a large tidal range; they occur around the times of full or new moon.
Neap Tides – The tides with a small tidal range. They occur around the times when the moon is in quarter.

d. How does tidal range effect the types of organisms and the shape and size of the organisms? I think the tidal range affects the types, shape and size of the organisms depending on their lifestyles. Below are a few samples of the differences in lifestyles and zones:
Intertidal
- unique among marine environments
- regularly exposed to the air
- organisms living here must have a way to cope with exposure
- Intertidal communities differ greatly depending on whether they have rocky or soft bottoms
- Plankton (Pelagic Organisms). Such organisms are sharks, dolphins, turtles and squids. These organisms are also called drifters because they move around a lot.
Subtidal
- part of the continental shelf
- never exposed at low tide
- consist of the bottom of the ocean from the low tide level to the shelf break (the outer edge of the continental shelf)
- Benthos (Benthic Organisms). Such organisms are stingrays, sessile, starfishes and sponges. These organisms live at the very bottom.

Student Notes Only: Intertidal (littoral) Zone – The area between the highest and lowest tide.
Subtidal (sublittoral) Zone – The bottom above the continental shelf.

CITE: picture obtained from http://www.mvariety.com/calendar/august/30/default.htm