Dna....and Its Many Questions!! (1 Viewer)

[Rippa]

heres just a few questions in relation to evolution ....see if u can have a go at it, becuase i was stumped with these following ones ...

1) Breifly describe the major contribution of each of these sientists to our understanding of biological evolution.
a) lamarck
b) Wallace
c) Darwin
d) stephen J Gould & Niles Eldridge
2)**Describe how X-ray crystallography was used to work out the molecular structure of DNA ( this one realy got me in a corner)

3)write a single sentence that uses each of the following terms at least once and describes their relationship to each other.
>amino acids >polypeptide >protein >gene
4) a)List and describe and evidence you can find that radiation causes mutations.
b)Describe 2 examples where human activity had produced mutagenic radiation.
c) Assess the impact that such radiation might have on an affected population.


Cheers....

 

[rhia]

3) write a single sentence that uses each of the following terms at least once and describes their relationship to each other.
>amino acids >polypeptide >protein >gene

each series of three nitrogenous bases on a gene, or a codon, provides the information for the synthesis of 1 of 21 existant amino acids, which form polypeptides which in turn form proteins.

4) a)List and describe and evidence you can find that radiation causes mutations.

there is a greater incidence of cancer, leukemia, and illness in individuals exposed to radiation: for example, those who work with radiation, an example being marie curie and her daughter irène: both victims of leukemia, both radiographers.

the experiments performed by beadle and tatum involved the mutating of the genes of bread mold using x-rays: karl sax similarly mutated plant chromosomes by the same means.

the ames test, developed by bruce ames, is a test that tests for the mutanogenic properties of chemicals on bacteria and, studies indicate that the majority of chemicals that act as mutanogens on bacteria also are mutanogenic to humans.

 

[ladyknight]

Oi Rippa, we're not here to do your work for you! If you want something to start you off, try

http://hsc.csu.edu.au/biology/core/blueprint/9_3_1/931net.html

for Darwin and Wallace, and

http://hsc.csu.edu.au/biology/core/blueprint/9_3_2/BIO934NET.htm

for dna structure-

http://www.pbs.org/wgbh/aso/databank/entries/do53dn.html

also helps outline the dna structure discovery, with some specific reference to Franklin's awesom contributions.

Cheers back ;D

 

[Dr_Doom]

Darwin proposed the theory of Natural Selection and Survival of the fittest. There are two types of evolution, convergent and divergent. The finches Darwin observed on the Gallapogas islands was an example of divergent evolution. As the birds had adapted to the particular environments of different islands and developed unique characteristics. They became so different that they wouldn't mate with other birds from other islands as they were practically a different species.

Don't really know what wallace did. All I think of is he helped propse the theory of Evolution...

The DNA structure is too long to explain.................

 

[k_stroud22]

well, rosalind franklin was the one who did the X-ray crystallography of DNA (which wallace and crick STOLE from her... its a long story...). when wallace and crick looked at the photograph of DNAs crystallography, the shape of the pattern showed that DNA was a double helix.

go to the website below to see a pic of it

http://www.pbs.org/wgbh/evolution/library/06/3/image_pop/l_063_01.html

 

[Dr_Doom]

She also figured out the the phosphates and sugars go on the outside of the the dna strand and the bases align in the middle with Cytosine > Guanine and Thymine to Adenine. And theres some base that starts with U that is only seen in RNA. I forget it though...

Hey also does anyone know what the difference is between codons and anti-codons? Like I kno the tRNA brings down the admino acid with it's anti-codon. But I don't see what the codons are for.........? Oh wait are codons the group of 3 nucleotides already connected to the mRNA?

 

[k_stroud22]

And theres some base that starts with U that is only seen in RNA. I forget it though...

its uracil

Oh wait are codons the group of 3 nucleotides already connected to the mRNA?

yeah, i think so. sry my 1/2 yearlys are on now, and bio's not till monday...i'm plannin gto revise on the weekend!

 

[Dr_Doom]

I'm trying to memorize each dot point. Or at least understand it lol

My exam is 2moro!

 

[Tim035]

Rippa your teacher must be using the exact same test or textbook as my school because we have an assingment which has those EXACT questions plus a dozen more... Orrr maybe you go to my school!?!?