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Bio paper/42

What would be the minimum marks required for A in bio/42 ?


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1.concentration of water molecules in a solution, like in blood :D
2. The mutation cause a change in base which now coded for a stop codon hence different primary structure smaller polypeptide chain so smaller mass of protein produces.
3.DNA contains gene for proteins, specific to only chloroplast. as chloroplast also conatin 70S ribosome so translation is done in the chloroplast for such proteins. But I named protein as example RUBISCO :D
4.I didn't attemt did Q9
5. as infants metabolic activities are less they donot produce enough heat by other processes, so BAT is there as BAT release heat energy by synthesis of ATP.

No no the question 2 was because, Mutation caused less "Protein" to be made the protein's function was to reduce cell differentiation and GROWTH so therefore less muscle mass. , i forgot the name of the protein they gave in the question also the function of the protein was given in the question.
 
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Optic nerve I mentioned the tumor blocking the light from entering the optical nerve. The receptor cells cant detect any light. Thus they dont pass any message to the brain.

LOL! Noo.

I wrote the tumor cells produce chemicals which act as inhibitor to the neurotransmitters and because of this the neurotransmitters cannot bind to the postsynaptic membrane so the action potentials are not generated. :p
 
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I hate to break it to you, but you seem to be wrong. The question clearly stated that when a person with NF has offspring, there is a 50% chance of an individual with NF being born. Work it out for yourself. If it was a recessive gene, it could only display itself in a homozygous recessive condition and so it would have a maximum 25% chance of the individual suffering from NF.

As for the second part of your question, the question stated, why is it that in some individuals who are not carriers of the disease an offspring may be produced which has the disease. The answer to this was that there is a chance of a mutation occurring. It had nothing to do with recessive genes.

No! What if the normal person was a carrier? Then? The cross would produce 50% of offspring being NF
Nn - Normal
nn- NF

Offspring produced will be - Nn , Nn , nn, nn (which matches with the criteria of the question)
So for that reason the allele is recessive.

If the allele for NF was Dominant then all the offspring produced will be NF positive or all NF positive but heterozygous.
or 75% NF positive. Which do not satisfy our question criteria.

Here are the possibilities of your criteria.

NN x NN
or NN - nn
or Nn x Nn (here only 25% will be normal rest will be 75% NF)

Will produce this :-

NN,NN,NN,NN
Nn,Nn,Nn,Nn
NN,Nn,Nn, nn

So for these reasons, i choose NF as recessive. :p
 
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There were many questions which i guessed !
Eg . tell me what you wrote for:
1- water potential definition
2- why CC has more muscle mass
3 - role of dna in chloroplast
4-processes for last question in section A
5-why infant has higher BAT
and many more !

1) Water potential is the number of free water molecules in a substance eg. blood.
2) CC has more muscle mass because it does not produce the protein (something starting with "m"). They say in the question that only the mutated gene produces that protein and since CC does not produce that protein which slows sown development and growth of muscle cells, horses with CC genotype will have a larger muscle mass. The muscle cells will definetely have a protein receptor for that protein so it acts as an inhibitor of muscle development and growth.
3) DNA used to make essential enzymes and protein for the chemical reactions of chloroplast. Used to make rubisco and ATP synthase.
4) Process 1 and 3 because they say at the top of the question that this mitochondria behaves differently than normal mitochondria in a cold environment so it is process 1 and 3. Process 1 pumps out H+ ions and process 3 brings in H+ ions releasing heat.
5) Infant has higher BAT because they are still growing and are sensitive to changing temperature. Moreover we have less as adults because we already have more of the other SAB fat surrounding our organs and underneath our skin!!! Hope this helps :D I may be wrong :p
 
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For anyone who still has a problem with the question related to Neurofibromatosis:
Neurofibromatosis type 1 is considered to have an autosomal dominant pattern of inheritance. People with this condition are born with one mutated copy of the NF1 gene in each cell. In about half of cases, the altered gene is inherited from an affected parent. The remaining cases result from new mutations in the NF1 gene and occur in people with no history of the disorder in their family.

It clearly states the answers to both of the questions. First of all, the allele for NF is definitely dominant. Secondly, as for the question about how a person could suffer from the disease if his/her parents were not carriers, it could arise from mutation.

Source: http://ghr.nlm.nih.gov/condition/neurofibromatosis-type-1
 
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For anyone who still has a problem with the question related to Neurofibromatosis:


It clearly states the answers to both of the questions. First of all, the allele for NF is definitely dominant. Secondly, as for the question about how a person could suffer from the disease if his/her parents were not carriers, it could arise from mutation.

Source: http://ghr.nlm.nih.gov/condition/neurofibromatosis-type-1
but the information given in the question wasnt enough to come to this conclusion
 
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guys what abt the question which says state precisely where ADH is secreted into the blood..i was confused when they have mentioned in the blood so
i wrote renal artery... is that correct?
 
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guys what abt the question which says state precisely where ADH is secreted into the blood..i was confused when they have mentioned in the blood so
i wrote renal artery... is that correct?
posterior lobe of pitutary gland :D
 
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No! What if the normal person was a carrier? Then? The cross would produce 50% of offspring being NF
Nn - Normal
nn- NF

Offspring produced will be - Nn , Nn , nn, nn (which matches with the criteria of the question)
So for that reason the allele is recessive.

If the allele for NF was Dominant then all the offspring produced will be NF positive or all NF positive but heterozygous.
or 75% NF positive. Which do not satisfy our question criteria.

Here are the possibilities of your criteria.

NN x NN
or NN - nn
or Nn x Nn (here only 25% will be normal rest will be 75% NF)

Will produce this :-

NN,NN,NN,NN
Nn,Nn,Nn,Nn
NN,Nn,Nn, nn

So for these reasons, i choose NF as recessive. :p
http://en.wikipedia.org/wiki/Neurofibromatosis
honey! please read it :D
 
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I you read the next question, They said "Explain how could the offspring of the parents get NF if both did not have NF"
This means the NF allele is recessive , The Parents were Carriers "Heterozygous".

So in the cross I put NF allele as recessive. "nn"

:D
bro!
There is one thing "Mutation" in Biological science :D please google it :D
 
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I wrote that chloroplasts have the DNA to divide by binary fission due to their link to prokaryotes am I write? :/
 
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Sorry bro but i dont think that would be right :s

The origin of chloroplasts is now largely accepted by the botany community as occurring via endosymbiosis on an ancestral basis with the engulfment of photosynthetic bacterium within the eukaryotic cell. Over millions of years the endosymbiotic cyanobacterium evolved structurally and functionally, retaining its own DNA and the ability to divide by binary fission (not mitotically) but giving up its autonomy by the transfer of some of its genes to the nuclear genome.

See this? Ref: http://en.wikipedia.org/wiki/Chloroplast_membrane
 
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