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General Thoughts: Biology (1 Viewer)

narutofire21

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i said it was a clone cause i remember tv doco where they 'cloned' different animals such as Dolly. In doing so they just took the genes/gamates from the original soi just bsed about meiosis and said it was a clone
 
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Ahh yeh that's right. I put D, the deep roots... I have that in my notes
I didnt really like that question because it's all kind of relative... because technically for the plant having extensive roots doesnt minimise water loss but rather increases water gathering ability, and I figured since water is lost through transpiration in the stomata in the leaves having smaller leaves would reduce loss. But its a bit of a dodge question
 

panakap

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I didnt really like that question because it's all kind of relative... because technically for the plant having extensive roots doesnt minimise water loss but rather increases water gathering ability, and I figured since water is lost through transpiration in the stomata in the leaves having smaller leaves would reduce loss. But its a bit of a dodge question
I agree with you there I actually initially put A which was the smaller leaves... not sure though
 

s-tressed

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Pretty easy tbh. The hardest part in section B part 2 was probably the fusing of egg cells for me... Defiantly got some sillies in MC that i'm disappointed with though. -.-
Communication was all good too :) Scared about the scaling and stuff though since it seems like everyone found it easy :(
 

sramisetty

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I was having doubts as well when I was answering that 5 marker, but it is right I spoke with my bio teacher after. He said that the ovum acts as the sperm carrying the other 23 chromosomes required to fertilise and since all the DNA belongs to the orignal female, then it must be a clone

I wrote that it would not be a clone; here is my understanding of the Q:

Due to independent assortment, each egg would be unique. For example, assume brown eyes (B) are dominant to blue (b). A person with heterozygous brown eye colour would have a genotype Bb. This person may have two eggs with the chromosome carrying the 'b' allele (remembering the number of chromosomes is halved during meiosis). Thus, these two eggs would form a 'bb' offspring with blue eyes - which isn't a clone.

Assuming it was a human, for it to be an EXACT clone, all chromosomes would need to match up exactly, which is a 1/(2^23) chance. Disregarding crossing over, this would be highly unlikely.
 

ushnakhalid

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What do you mean the genetics was literally the easiest they could make it. No cloning, selective breeding, barely anything on gene expression, nothing on HOX genes and the like. It was a pleasant paper :)
everything you mentioned is what i love! i couldve written an 8 marker on selevtive breeding or cloning haha
 

Dabest

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It was not a clone. U got to know that The gametes may have any allele from mother. Let's say for eye colour the mother genotype is Bb(B is dominant for brown, b is recessive for blue) each gamete will either have the B or b allele, but not both as it is a haploid cell(obviously) so by chance (1/4) the two gametes may have just b allele so when the combine the genotype would be bb meaning blue eyes, which is different to mother.
P.s. Derrick is an idiot
 

s-tressed

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I didnt really like that question because it's all kind of relative... because technically for the plant having extensive roots doesnt minimise water loss but rather increases water gathering ability, and I figured since water is lost through transpiration in the stomata in the leaves having smaller leaves would reduce loss. But its a bit of a dodge question
I put A (smaller leaves) as well.
 

s-tressed

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wtf how was it a clone

"use your understanding of genetics"

- crossing over = variation. therefore not a clone
- possibility of mutation = variation. therefore not a clone
- random segregation = variation. therefore not a clone.
- fertilisation of egg = variation. therefore not a clone.
AGREED! yay! (I think).
 

Zeref

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wtf how was it a clone

"use your understanding of genetics"

- crossing over = variation. therefore not a clone
- possibility of mutation = variation. therefore not a clone
- random segregation = variation. therefore not a clone.
- fertilisation of egg = variation. therefore not a clone.
Well well well. Let the arguments start
 

alex4nder

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I wrote that it would not be a clone; here is my understanding of the Q:

Due to independent assortment, each egg would be unique. For example, assume brown eyes (B) are dominant to blue (b). A person with heterozygous brown eye colour would have a genotype Bb. This person may have two eggs with the chromosome carrying the 'b' allele (remembering the number of chromosomes is halved during meiosis). Thus, these two eggs would form a 'bb' offspring with blue eyes - which isn't a clone.

Assuming it was a human, for it to be an EXACT clone, all chromosomes would need to match up exactly, which is a 1/(2^23) chance. Disregarding crossing over, this would be highly unlikely.
:headbang: My reasoning as well
 

nicolioo

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for question 15, the one about goltz syndrome, was just curious what everyones punnet squares were like as mine showed the girl to be a carrier rather than have the the syndrome and the boy had nothing ?
i still put D but am just curious if the answer is d because it is inherited as a dominant gene ??
 

bengosha60

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i think i messed up the observation of the rat thing :L put vasoconstriction but you cant really observe it... what else did you guys put?
 

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