Who's feeling competitive? (1 Viewer)

[Sarks]

Greetings young, upright, bipedal, large brained mammals.

Biology enthusiasts, who wants a little competition? See who comes up with the best answers to any question you feel the need to post!
Simply to see what levels people are at, help out others and give us an idea of how hard we need to study. Remember, NO GOOGLING ANSWERS!

Ill start us off, shall I, a nice easy one about genetics and mutation J

Jim’s father has brown eyes, his mother has green eyes.
Jim was born with one eye brown-blue and the other just brown.
This mutation likely occurred in which of the following:
A) Sperm
B) Ova
C) Zygote
D) Embryo

 

[samthebear]

i dont know this, but i'll take a stab and say the answer is C) Zygote

and isnt this thread like the 2009 Biology Marathon thread?

 

[Sarks]

Yea, theres a similar thread to this one, but i wanted to start a new one coz i didnt like the other one.

Ill reveal the answer once some more people have had a go

 

[brenton1987]

i dont know this, but i'll take a stab and say the answer is C) Zygote

A zygote is simply a fertilised egg. Since no cell differentiation has occured any mutation occuring at the zygote stage is going to be expressed in both eyes.

 

[Survivor39]

I'm not 100% sure but I think it might be "A".

 

[xandersnape]

Il say C......

however Im not so good at bio

 

[9876543210]

B?
im not too sure about this..

 

[phayte]

its got to do with dominant and recessive alleles..?
A or B.
idk which though

 

[ekoolish]

It's A aih?

 

[Brandonn]

i Shall Say its an A !

 

[hvf26]

lol did this question in bio the other day

its D, not C (zygote is a fertilised egg, theres no cell differentiation to make the eyes and what not) hence its the embryo, as the mutation wouldve occured after eyes had been developed

 

[Chemical Ali]

Well, what makes eyes blue or brown? Brown is the presence of a pigment, blue is just its absence.

If there was a mutation in the sperm which deleted the ability to make the pigment, his eyes should be entirely green/blue, since his mum must be homozygous in order not to be brown.

If the mutation occured in the ova, his eyes would be brown still

If the mutation occured in the zygote, either
a) in the copy from his mum --> same as for ova
b) in the copy from his dad --> same as for sperm

therefore the only possibility that could explain that phenotype would be a mutation in the embryo, as the poster above says