29
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Solving Hardy Weinberg problems
Here is a tutorial to perfectly understand Hardy-Weinberg Rule! If you feel like you just need a brief reminder, you can skip the text until the section In short... and try out the exercises just to ...
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Frequency of dominant phenotype (Hardy-Weinberg)
p = p(a) = 0.6
q = p(A) = 0.4
Frequency of homozygous recessive, aa = p2 = 0.36
All other genotypes have dominant phenotype therefore the frequency of the dominant phenotype is 1-0.36 = 0.64
(...
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7
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Solving Hardy Weinberg problems
Lets say there are 2 alleles. One of them is represented by B and other by b. Both will have some frequency at a specific time in a population. Now, frequency is number of that allele divided by total ...
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5
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Accepted
Question regarding the number of alleles
The two-allele scenario is often used in genetics teaching because of its simplicity. However, quite a few genes have more than two alleles. Some examples that readily come to mind are:
The ABO gene ...
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4
votes
Accepted
Hardy Weinberg principle
You almost said it all! Here are two ways to think of this problem
Finding the missing probability
Let's denote the fraction yz genotype in the population with $f(...
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Hardy-Weinberg Equilibrium help
I think what question 2 is trying to imply is that only homozygotes for brown alleles are brown skinned. But if the heterozygote has a different phenotype from the homozygotes, I don't see how it is ...
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Hardy-Weinberg Equilibrium help
You are correct and the instructor in the second video should have used p^2 + 2pq = 0.64. The only reason I can think of for leaving out the 2pq term is if the heterozygous individuals do not have ...
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Re-establishment of Hardy Weinberg Equilibrium After Selection
Revised to add complete solution
Before the owls arrive, 100 out of the 2500 mice are dark-colored. This ratio provides the frequency of the recessive allele
$$q^2 = \frac{100}{2500}$$
So $q$ is 10/...
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Hardy Weinberg equilibrium
Carrier females= 2pq= 2 x .08 x 0.92
Because carriers say with genotype Aa (A=dominant, a=recessive) can arise due to two types of inheritances;one when A is from father and a is from mother and ...
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Hardy-Weinberg sex linked formula
Solving Hardy-Weinberg problems
First of all, you might want to have a look at the post
Solving Hardy-Weinberg problems
and eventually at
Assumptions of Hardy-Weinberg rule
After reading the first ...
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Hardy Weinberg Clarification
the population tends towards infinity
Well yes, Hardy–Weinberg principle is based on several assumptions one of them being "population size is very(infinitely) large". Another being "Mating is random"...
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For allele frequency determination, is it good to take samples from a college/school or a hospital or any other technique?
I suggest this as a starting point.
Basically, if your aim is to determine the population frequency of the alleles, then you should sample from the population.
A possible problem with the university ...
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What is difference between Incest and Inbreeding?
Incest is a human concept defined by law and social conventions. For example, see a definition of the word: "sexual intercourse between persons so closely related that they are forbidden by law to ...
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Accepted
What does it mean when observed genotype frequency is different from expected genotype frequency in Hardy-Weinberg equilibrium?
From Wikipedia, bold added by me:
In population genetics, the Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem, or law, states that allele and genotype ...
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Accepted
Hardy-Weinberg principle
I can't think of a more succinct way to phrase it than the explanation in your post.
"...the genotype frequencies of the next generation depend only on the
allele frequencies of the current ...
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Question regarding the number of alleles
Depending at which level you are defining an allele. As @Adhish described, at the molecular level there is no theoretical limit on the number of alleles of a given gene. The presence or not of more ...
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Linkage between chromosomal loci and the Hardy-Weinberg principle
Linkage is a physical reality
Linkage refers to the physical presence of several loci on the same chromosome. Two loci that are said to be in close linkage mean that they are locataed relatively ...
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How many birds in this population would be expected to have either red or white feathers?
The solution
$$p^2 = 202 / 630 ≈ 0.32$$
$$p = \sqrt{202/630}$$
$$(1-p) = 1 - \sqrt{202/630}$$
$$(1-p)^2 = \left(1 - \sqrt{202/630}\right)^2 ≈ 0.188$$
There is a fraction of $202 / 630 ≈ 0.32$ of red ...
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What are the differences in the two possible methods to calculate the Hardy-Weinberg Equation?
You are throwing numbers into an equation without understanding it.
If you know the numbers for pp, pq and qq, you don't use HWE to recalculate them. So your last statement in Calculation 1 is ...
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What are the differences in the two possible methods to calculate the Hardy-Weinberg Equation?
Okay, so the Hardy-Weinberg Equilibrium is just that: an equilbrium.
In physics, a system (some object) is at equilibrium when no net energy crosses its boundary with the surroundings.
no energy ...
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Finding for evolution, comparing past flower numbers with present
You see a question like this, you should just go ahead and calculate if the population is in Hardy-Weinberg Equilibrium, because that's almost certainly what's going to be asked.
For 10 years ago: ...
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Finding for evolution, comparing past flower numbers with present
Has there been evolution in this population?
If $p$ differs in the population, then yes. If you $p_1$ and $p_{10}$ (the two different estimates at generation 1 and generation 10) are equal, then any ...
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Hardy Weinberg Explanation
The answer is logical if you understand the reasoning behind Hardy-Weinberg. I recommend that you to have a look at the post Solving Hardy Weinberg problems and try to answer the question yourself. ...
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X Linked Hardy Weinberg Equilibrium Problem
In a given population, 40% of men have hemophilia – an X-linked recessive disorder. What are the odds that a random woman and a random man from that population will have a daughter with hemophilia?
...
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