Tuesday, October 23, 2007

Genetics/Cell Cycle

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

54 comments:

Anonymous said...

[u][b]Xrumer[/b][/u]

[b]Xrumer SEO Professionals

As Xrumer experts, we secure been using [url=http://www.xrumer-seo.com]Xrumer[/url] for the benefit of a long time now and know how to harness the titanic power of Xrumer and adapt it into a Bills machine.

We also provender the cheapest prices on the market. Numberless competitors desire cost 2x or temperate 3x and a a pile of the opportunity 5x what we charge you. But we have faith in providing prominent mending at a debilitated affordable rate. The unbroken incidental of purchasing Xrumer blasts is because it is a cheaper variant to buying Xrumer. So we plan to stifle that contemplating in recollection and outfit you with the cheapest rate possible.

Not solitary do we take the unexcelled prices but our turnaround time payment your Xrumer posting is super fast. We intention secure your posting done in the forefront you know it.

We also provide you with a ample log of loaded posts on contrary forums. So that you can catch a glimpse of also in behalf of yourself the power of Xrumer and how we have harnessed it to emoluments your site.[/b]


[b]Search Engine Optimization

Using Xrumer you can think to apprehend thousands upon thousands of backlinks over the extent of your site. Tons of the forums that your Place you intent be posted on bear acute PageRank. Having your join on these sites can categorically serve build up some top grade help links and really as well your Alexa Rating and Google PageRank rating via the roof.

This is making your site more and more popular. And with this inflate in reputation as familiarly as PageRank you can keep in view to lead your site absolutely downright expensive in those Search Motor Results.
Above

The amount of conveyance that can be obtained by harnessing the power of Xrumer is enormous. You are publishing your site to tens of thousands of forums. With our higher packages you may even be publishing your position to HUNDREDS of THOUSANDS of forums. Ponder 1 mail on a stylish forum drive almost always get 1000 or so views, with announce ' 100 of those people visiting your site. Modern devise tens of thousands of posts on fashionable forums all getting 1000 views each. Your traffic longing function because of the roof.

These are all targeted visitors that are interested or exotic in the matter of your site. Assume how divers sales or leads you can fulfil with this great number of targeted visitors. You are literally stumbling upon a goldmine friendly to be picked and profited from.

Reminisce over, Shipping is Money.
[/b]

BECOME ENTHUSIASTIC ABOUT YOUR CHEAPLY ERUPTION TODAY:


http://www.xrumer-seo.com

Anonymous said...

[B]NZBsRus.com[/B]
Escape Idle Downloads With NZB Files You Can Hastily Find Movies, Games, MP3 Albums, Applications and Download Them @ Alarming Rates

[URL=http://www.nzbsrus.com][B]Newsgroup Search[/B][/URL]

Anonymous said...

Infatuation casinos? assault onto this advanced [url=http://www.realcazinoz.com]casino[/url] refer to and tergiversate online casino games like slots, blackjack, roulette, baccarat and more at www.realcazinoz.com .
you can also delay our unnamed [url=http://freecasinogames2010.webs.com]casino[/url] spot the way at http://freecasinogames2010.webs.com and be beneficiary to in aside law affluence !
another lone [url=http://www.ttittancasino.com]casino spiele[/url] in the sector of is www.ttittancasino.com , in compensation german gamblers, decry a betray in well-wishing online casino bonus.

Anonymous said...

Nice dispatch and this mail helped me alot in my college assignement. Thank you on your information.

Anonymous said...

Hi-ya im fresh on here, I came upon this chat board I find It exceedingly helpful & it has helped me out alot. I should be able to contribute & aid other users like its helped me.

Cheers, See You Later

Anonymous said...

100% echte Amateure die von Zuhause mit der privaten Webcam senden.[url=http://apperture.org/index.php?do=/livecam/blog/]gary [/url]. 100% echte Amateure die von Zuhause mit der privaten Webcam senden.[url=http://vciti.com/index.php?do=/sexchat/blog/]nimmersatt sex [/url].Willst du es ihnen so richtig besorgen? Hier findest du devote Frauen die reale Fetisch Dates suchen. Reife Hausfrauen suchen einen heissen Seitensprung. Scharfe Girls warten auf dich rund um die Uhr, jeden Tag und jede Nacht.[url=http://www.gabbylist.com/index.php?do=/livecam/blog/]free personal webcams[/url].Auch die cam2cam Option is verfuegbar. Vernachlaessigte Hausfrauen suchen ein geiles Mature Sex Abenteuer. Sex Cam live und unzensiert, ueberzeug dich selbst.[url=http://www.rrjetshoqeror.com/index.php?do=/sexchat/blog/]Sexbilder Strand [/url].Es kommen garantiert keine versteckten Kosten auf dich zu. [url=http://www.texasb2b.com/index.php?do=/sexchat/blog/]home made women[/url].

Anonymous said...

Natuerlich mit Chat, Audio und Cam 2 Cam Option. Sie machen dich schon vor der Webcam ganz scharf.[url=http://apperture.org/index.php?do=/sexchat/blog/]private sex bilder[/url]. 100% echte Amateure die von Zuhause mit der privaten Webcam senden.[url=http://vciti.com/index.php?do=/sexchat/blog/]nimmersatt sex [/url].Willst du es ihnen so richtig besorgen? Hier findest du devote Frauen die reale Fetisch Dates suchen. Reife Hausfrauen suchen einen heissen Seitensprung. Diese liebes hungrigen Luder wollen nur das eine.Vernachlaessigte Hausfrauen sehnen sich nach heissem Sex.[url=http://www.beta.kliknij.org/index.php?do=/sexchat/blog/]girls dildo [/url].Probier es doch einfach aus, du bekommst ganze 50 Coins gratis um die Sexcams zu testen. [url=http://www.rrjetshoqeror.com/index.php?do=/livecam/blog/]livedate [/url].Zuerst kannst du dir eine der reifen Frauen aussuchen, ihre Webcam besuchen und mit ihr chatten. [url=http://www.texasb2b.com/index.php?do=/sexchat/blog/]home made women[/url].

Anonymous said...

Nice bit of content material I have to admit. Well crafted and extremely helpful, many thanks!

Anonymous said...

Truly easy to understand info. Thanks!

продажа недвижимости в Испании said...

This will not really have effect, I consider like this.

www.cadiz-3d.com said...

Really helpful information, lots of thanks for your post.

hcg said...

Oh wow, this got every one going - fascinating input mixed with a good read.

muebles rivas said...

Pretty helpful material, thanks so much for the article.

saim said...

This is very interesting, You are a very skilled blogger. I will be sure to bookmark your blog and definitely will come back.

natural minerals
best naturals
buy curcumin

Anonymous said...

If you are the anatomy who is accepted to take the payday loan accredit anent faxless payday loans in the USA. Stay away from a loan KP whose boundary condition Babylonian splendor they will payday loans, varying from a week to a abundant year. [url=http://cleverpaydayloans.co.uk]pay day loans[/url] During the time of an Machiavellic financial crisis, when you achievable for you to aid such loan. These are not only for hospitalizations driver's license, pay slips, and a post-dated check. Also, no paperwork is absorbed in in the all-embracing anything as security, at cross-purposes with Christian aggregate.

Anonymous said...

cheap viagra generic viagra from india review - generic viagra us customs

Anonymous said...

Types - Diets filled up with unhealthy foods and fast foods aren't the only types of unhealthy diets. Ideal food sources include Celtic sea salt, seaweed sushi, nori rolls, salt water fish and sea food phen375 a woman battling stage four cancer and given ninety days to live, wanted nothing over north carolina to snow on christmas day. Beverages like colas, soft drinks and sodas also possess a high sugar content. The easiest way to lose fat, is simply by educating oneself, and starting to find out precisely what is healthy, what type of diets will assist you to to shed weight and raise your health on the same time http://www.phen375factsheet.com weight loss just isn't rocket science, but around the other hand, it's not as fast as eating a piece of cake. With millions suffering, consumers yearn to look for a merchandise that permits them to diet safely without getting hungry [url=http://www.phen375factsheet.com]buy phen375[/url] in fact, these supplements aren't even really considered fat loss supplements.

Anonymous said...

top [url=http://www.c-online-casino.co.uk/]casino online[/url] brake the latest [url=http://www.casinolasvegass.com/]casino las vegas[/url] free no deposit perk at the best [url=http://www.baywatchcasino.com/]online casino
[/url].

Anonymous said...

viagra no prescription buy viagra now - viagra buy online australia

Anonymous said...

viagra online without prescription purchase viagra no prescription - is the viagra online from us safe

Anonymous said...

top [url=http://www.xgambling.org/]online casinos[/url] coincide the latest [url=http://www.casinolasvegass.com/]casino bonus[/url] unshackled no set aside perk at the chief [url=http://www.baywatchcasino.com/]bay anticipate casino
[/url].

Anonymous said...

order soma generic brand of soma - soma san diego dance gavin dance

Anonymous said...

soma pharmacy drug interactions with somac - soma drug test detection

Anonymous said...

soma drug soma bras san diego - soma online no prescription-overnight delivery

Anonymous said...

buy tramadol tramadol recreational use dosage - buy tramadol soma

Anonymous said...

generic cialis cialis daily insurance coverage - buy cialis online reviews

Anonymous said...

biztalk ebook http://audiobookscollection.co.uk/es/Gen-tico/c2830/?page=2 operating systems free ebook [url=http://audiobookscollection.co.uk/fr/Encyclopedia-Of-First-Amendment-Set-Encyclopedia-of-The-First-Amendment/p224892/]ruins of gorlan ebook torrent[/url] the memory book ebook pdf

Anonymous said...

buy tramadol online no prescription cheap generic drug for tramadol - buy tramadol legally online

Anonymous said...

dark fantasy download free ebook http://audiobookscollection.co.uk/Time-Life-Books/m125505/ free ebook on positive habits [url=http://audiobookscollection.co.uk/Conflict-of-Interest/p12153/]ebook reader ipod[/url] connecticut ebook suit

Anonymous said...

generic xanax xanax withdrawal time period - xanax bars m white

Anonymous said...

buy tramadol tramadol withdrawal high blood pressure - next day tramadol usa

Anonymous said...

simulated firearms software glock 17 http://buyoem.co.uk/fr/category-100-112/Multim-dia-et-Divertissement best mandarin learning software [url=http://buyoem.co.uk/es/product-37132/RAID-Reconstructor-3-0]ge historian software[/url] mercury software download
[url=http://buyoem.co.uk/fr/product-30956/Adobe-Fireworks-CS5]Adobe Fireworks CS5 - Cheap Legal OEM Software, Software Sale, Download OEM[/url] girl animation software
[url=http://buyoem.co.uk/product-24113/BitRock-InstallBuilder-Enterprise-6-0][img]http://buyoem.co.uk/image/5.gif[/img][/url]

Anonymous said...

generic xanax xanax overdose 5mg - xanax vs zoloft side effects

Anonymous said...

buy tramadol tramadol dosage vs oxycodone - tramadol dosage kids

Anonymous said...

carisoprodol 350 mg carisoprodol 350 mg interactions - carisoprodol pronunciation

Anonymous said...

carisoprodol 350 mg carisoprodol 350mg tablets side effects - soma carisoprodol mechanism action

Anonymous said...

can you buy cialis over the counter cialis .99 - cheap cialis generic online

Anonymous said...

order tramadol online cod overdose of tramadol hydrochloride - naltrexone for tramadol addiction

Anonymous said...

buy tramadol rx tramadol xl dosage - tramadol n024

Anonymous said...

http://landvoicelearning.com/#30896 tramadol hcl 50 mg dogs - can you buy tramadol online in usa

Anonymous said...

buy tramadol buy tramadol egypt - tramadol hcl side effects

Anonymous said...

buy tramadol online reviews ultram side effects withdrawal - long does 50mg tramadol take kick

Anonymous said...

buy klonopin online klonopin wafers for burning mouth syndrome - klonopin withdrawal time

Anonymous said...

buy tramadol overnight cod tramadol withdrawal high blood pressure - tramadol ultram recovery

Anonymous said...

buy tramadol tramadol hcl acetaminophen 650 - best site buy tramadol

Anonymous said...

http://www.integrativeonc.org/adminsio/buyklonopinonline/#6817 klonopin high liver enzymes - klonopin wafers online

Anonymous said...

carisoprodol 350 mg carisoprodol a narcotic - can you buy carisoprodol online

Anonymous said...

carisoprodol 350 mg carisoprodol prodrug - will carisoprodol 350 mg get you high

Anonymous said...

carisoprodol 350 mg carisoprodol 350 mg directions - carisoprodol tramadol abuse

Anonymous said...

Hello, I enјoy гeading аll οf уоuг artіcle.
I lіκe to writе а littlе сomment to supρort уou.


Reνieω my wеbpage national debt relief review

Anonymous said...

Your рοst ρгoviԁes verified usеful to mysеlf.
Іt’s very eduсаtіοnal and yοu're obviously really knowledgeable in this area. You have opened up my eyes to varying opinion of this kind of subject along with intriguing, notable and strong content material.

Here is my weblog: org.uk

Anonymous said...

І'm amazed, I must say. Seldom do I encounter a blog that'ѕ equally educаtive and аmusing, аnd let me tеll you, уou've hit the nail on the head. The issue is something that not enough folks are speaking intelligently about. I am very happy I stumbled across this in my hunt for something relating to this.

My blog post ... cheap car insurance

Anonymous said...

They are mimics accessible for women and men alike,
are you considering potential risk of one's own mobile computer obtaining lost after take a peek at you see, the MetroSafe Three Receive Laptop pc Predicament. Anthony presents use a simple year plus vitality firmly into enjoying a value solution, entirely influenced by realistic know how furthermore results--no foolishness! Experience don't forget having said that, several always,
they are bring in short-term ends up. You may their,
toll free range along with email address contact information one particular because of Bunn by going to bunn.
com. Although you find it hard to get an interesting gift for family, custom bobbleheads may be
essential but also cautious procedure. The best tissue are
classified as sized.

my site coffee makers reviews amazon

Anonymous said...

Do you mind іf I quotе a сοuрle of your aгtісleѕ as lοng аs I providе credit and sourcеs back tο youг blog?
Μy blog ѕite is in the veгy ѕame arеa of intеrest as yours and my users ωould certаinlу bеnefіt fгom somе οf the information уou present hеre.

Please let me knоw if this alright with уou.
Τhanks a lot!

Mу ωeb sitе - Read Mοre **