Biology 2013ers MARATHONN (4 Viewers)

[Menomaths]

LOL!

 

[obliviousninja]

shhh I don't do bio I'm trying to fit in

New idea for belonging creative, Sy doesn't fit in on bio forum.

 

[Youi_]

New idea for belonging creative, Sy doesn't fit in on bio forum.

I see the 15/15 already

 

[Menomaths]

How could a mutation in DNA affect polypeptide production?

 

[Youi_]

How could a mutation in DNA affect polypeptide production?

During polypeptide synthesis DNA is copied onto messenger RNA. If the DNA undergoes a mutation the base sequence copied could be changed and could result in a non functioning amino acid and a polypeptide that will not fulfil its purpose.

Refine this answer I know it could be better

 

[Carrotsticks]

I did Biotechnology. Was really really fun.

 

[superSAIyan2]

During polypeptide synthesis DNA is copied onto messenger RNA. If the DNA undergoes a mutation the base sequence copied could be changed and could result in a non functioning amino acid and a polypeptide that will not fulfil its purpose.

Refine this answer I know it could be better

I dont think the amino acid is non-functioning. Rather the incorrect amino acid sequence is transcribed onto the mRNA strand. Hence the incorrect polypeptide is formed during translation ---> the resultant protein is dysfunctional.

Also you could say some point mutations (e.g. where a single base may be substituted by another) have no impact on polypeptide synthesis. This is because even though the mRNA base sequence is slightly changed, it may still code for the same amino acid sequence.

 

[Youi_]

I dont think the amino acid is non-functioning. Rather the incorrect amino acid sequence is transcribed onto the mRNA strand. Hence the incorrect polypeptide is formed during translation ---> the resultant protein is dysfunctional.

Also you could say some point mutations (e.g. where a single base may be substituted by another) have no impact on polypeptide synthesis. This is because even though the mRNA base sequence is slightly changed, it may still code for the same amino acid sequence.

Yeah that sounds a lot better

Describe the stages of meiosis and how they increase variation within a species

 

[ocatal]

Describe the contributions of MacFarlane Burnet to our understanding of the immune response.

 

[bedpotato]

Describe the contributions of MacFarlane Burnet to our understanding of the immune response.

MacFarlane Burnet studied the ways by which the body defends itself against invasion by foreign materials without attacking itself. His colonal selection theory helped us gain a better understanding of the immune system and how it recognises its own cells from foreign material. The colonal selection theory states that all the B and T cells for all the possible antigens are already present in the body in very small amounts, and when an antigen is present in the body, the B and T cells that correspond to that antigen are activated and cloned to destroy the pathogen.

Question: How does the lymph system act as a non-specific defense adaptation?

 

[ocatal]

MacFarlane Burnet studied the ways by which the body defends itself against invasion by foreign materials without attacking itself. His colonal selection theory helped us gain a better understanding of the immune system and how it recognises its own cells from foreign material. The colonal selection theory states that all the B and T cells for all the possible antigens are already present in the body in very small amounts, and when an antigen is present in the body, the B and T cells that correspond to that antigen are activated and cloned to destroy the pathogen.

Question: How does the lymph system act as a non-specific defense adaptation?

Careful.. It is 'clonal' selection theory.

The lymphatic system is a system of vessels containing a fluid called lymph. The system consists of several macrophage-containing lymph nodes which the lymph passes through. This acts as a form of non-specific defence as any foreign particles in the lymph are engulfed by the macrophages.

Outline how a change in chemical conditions in the environment impacts the evolution of plants and animals.

 

[superSAIyan2]

Changes in an environment's chemical composition acts as a selective pressure to favour the survival of organisms with certain variations over others, thus leading to a population's change in the frequency of alleles (evolution) by natural selection.

E.g. Insecticide resistance: DDT was used to reduce malaria by killing mosquitoes---> this change in chemical conditions favoured the survival of naturally resistant mosquitoes ---> non-resistant mosquitoes die, resistant mosquiotes survive and reproduce to pass on resistnat gene to offspring --> increased frequency of resistant gene in population by natural selection ---> developed resistance against DDT

Describe, using examples, how evidence from biochemistry has validated the theory of evolution.

 

[Youi_]

Changes in an environment's chemical composition acts as a selective pressure to favour the survival of organisms with certain variations over others, thus leading to a population's change in the frequency of alleles (evolution) by natural selection.

E.g. Insecticide resistance: DDT was used to reduce malaria by killing mosquitoes---> this change in chemical conditions favoured the survival of naturally resistant mosquitoes ---> non-resistant mosquitoes die, resistant mosquiotes survive and reproduce to pass on resistnat gene to offspring --> increased frequency of resistant gene in population by natural selection ---> developed resistance against DDT

Describe, using examples, how evidence from biochemistry has validated the theory of evolution.

Biochemistry has supported the theory of evolution via a study of the DNA of humans and chimpanzees which showed a 97% similarity in DNA. This supports the notion that we evolved from a common ancestor.

 

[superSAIyan2]

^asks for exampleS - more than one is needed/ Also try to be more specific; rather than simply saying study DNA, it is better to say the different methods used (what are they comparing between organisms)
E.g. through dna seuqencing it has been determined that the regulatory genes in insects and mammals share 80-90% similarity. This supports the theory's prediction that they share common ancestry.

analysis of chromosome banding patterns and gene linkage groups (which perform similar functions in closely related organisms) has verified a close evolutionary patterns between rats and mice

amino acid sequencing of vital proteins such as Haemoglobin and cytochrome-c has shown a great degree of similarity between humans, chimps and gibbons, this supports the concept of divergent evolution and has been used to estimate the period of divergence between the organsims

 

[jk412]

^asks for exampleS - more than one is needed/ Also try to be more specific; rather than simply saying study DNA, it is better to say the different methods used (what are they comparing between organisms)
E.g. through dna seuqencing it has been determined that the regulatory genes in insects and mammals share 80-90% similarity. This supports the theory's prediction that they share common ancestry.

analysis of chromosome banding patterns and gene linkage groups (which perform similar functions in closely related organisms) has verified a close evolutionary patterns between rats and mice

amino acid sequencing of vital proteins such as Haemoglobin and cytochrome-c has shown a great degree of similarity between humans, chimps and gibbons, this supports the concept of divergent evolution and has been used to estimate the period of divergence between the organsims

Shut up you fgt

 

[superSAIyan2]

^ No eco assholes on this thread. It destroys the purity of bio

 

[hayabusaboston]

^ No eco assholes on this thread. It destroys the purity of bio

Wasnt expecting u to swear LOL

Dang sai, u iz really heading for dat 99.95....

 

[Menomaths]

^ No eco assholes on this thread. It destroys the purity of bio

Bio has pathogens doe

 

[superSAIyan2]

Lol thats not really swearing. Also he's a fellow HAHS'er

 

[superSAIyan2]

Bio has pathogens doe

But we know how to get rid of pathogens!!! Well, most.