## Hardy-weinberg equation :D

Genetics as it applies to evolution, molecular biology, and medical aspects.

sweetxd
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### Hardy-weinberg equation :D

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

MrMistery
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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?
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

sweetxd
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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!

MrMistery
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hey no prob, i like to see people that actually do the work by themselves
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

sweetxd
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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

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

mith
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9/30?
Living one day at a time;
Enjoying one moment at a time;
Accepting hardships as the pathway to peace;
~Niebuhr

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

MrMistery
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that does not follow Hardy Weinberg
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

sdekivit
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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

MrMistery
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hey sdekivit. haven't seen you around for some time..
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

sdekivit
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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

Oscerot
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Wow.

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

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