Hardy-weinberg equation :D

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sweetxd
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Hardy-weinberg equation :D

Post by sweetxd » Tue Jan 09, 2007 8:50 pm

hey!
i have 2 questions.

1. In a certain population, the dominant phenotype of a certain trait occurs 91% of the time. What is the frequency of the dominant allele?

i got 0.7 or 70%...
it's either that or 0.91
i'm not sure.
which one do u think it is?


2. The allele for the hair pattern called widows peak is dominant over the allele for no widow’s peak. In a population of 1000 individuals, 510 show the dominant phenotype. How many individuals would you expect of each of the possible three genotypes for this trait?

Okay so i got
homozygous dominant 90
heterozygous 420
homozygous recessive 490

it's that.. or...

510, 410, 80 (respectively)

can someone please check my answers... and check which ones are right?


thank you so much! i appreciate it greatly :)


Here are some of hte equations
p + q = 1
p^2 + 2pq + q^2

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Post by MrMistery » Tue Jan 09, 2007 8:59 pm

1. it's 0.7. i can explain if you want
2. P-dominant; p-recessive
PP-90
Pp-420
pp-490

I can also explain. It is easy. Or do you understand?
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Post by sweetxd » Tue Jan 09, 2007 9:02 pm

thanks! yeah i understand... i just got confused at first. when they say dominant - that includes heterozygotes too.
i just wanted to make sure my answers were correct. thank you again! :)

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Post by MrMistery » Tue Jan 09, 2007 9:17 pm

hey no prob, i like to see people that actually do the work by themselves :lol:
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Post by sweetxd » Tue Jan 09, 2007 9:33 pm

lol yeah

one more thing,

if
AA - 6
Aa - 9
aa - 0
---------
15

then how do u find p and q.
because... since the recessive is 0.. there shoudl still be a q. but if u find the square root of 0 it'll be 0. but there should still be q in the heterozygotes. so q can't be = to 0... the recessive allele should never completely be removed bc of the heterozygotes... can someone clarify i'm confused :cry:

would u do 9/15 = 0.6 / 2 = 0.3/ 0.4 = 0.75?.. ahah i.. idk

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Post by mith » Tue Jan 09, 2007 11:18 pm

9/30?
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Enjoying one moment at a time;
Accepting hardships as the pathway to peace;
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Post by sweetxd » Tue Jan 09, 2007 11:48 pm

ohh.. is that for p or q? lol thanks

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Post by MrMistery » Wed Jan 10, 2007 3:08 pm

that does not follow Hardy Weinberg
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Post by sdekivit » Fri Jan 12, 2007 8:59 am

sweetxd wrote:lol yeah

one more thing,

if
AA - 6
Aa - 9
aa - 0
---------
15



now p and q are allel frequencies, thus theallele frequency q vcomes from the heterozygous individuals 9/30 as already said

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Post by MrMistery » Fri Jan 12, 2007 1:22 pm

hey sdekivit. haven't seen you around for some time..
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Post by sdekivit » Sat Jan 13, 2007 7:28 pm

MrMistery wrote:hey sdekivit. haven't seen you around for some time..


true --> was very,very busy studying the mechanisms of metabolic regulation the past 7 weeks. It was very annoying to get it all in my brains :roll: :lol:

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Post by Oscerot » Sat Jan 13, 2007 7:38 pm

Wow.

I just learned this yesterday in my grade 12 Academic Biology class. :lol: Got a bunch of questions to go along with it. :lol:

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