thebillsfan

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What is the difference between gene drift and gene flow? I don’t understand why the Founder effect cannot be an example of either/or

What’s the difference between and ionophore and an ion channel?

Would the eardrum be considered a part of the outer or middle ear?

How do you know if a 1:2:1 ration in a punnett cross is caused by incomplete dominance or by linked genes?

If a barr body forms on a X chromosome that is wild type for a gene leaving a mutant gene on the uncondensed chromosome, would the woman would get the disease? If the answer is yes, then why do x-linked diseases affect men only?
 
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What is the difference between gene drift and gene flow? I don't understand why the Founder effect cannot be an example of either/or

What's the difference between and ionophore and an ion channel?

Would the eardrum be considered a part of the outer or middle ear?

How do you know if a 1:2:1 ration in a punnett cross is caused by incomplete dominance or by linked genes?

If a barr body forms on a X chromosome that is wild type for a gene leaving a mutant gene on the uncondensed chromosome, would the woman would get the disease? If the answer is yes, then why do x-linked diseases affect men only?
The ear drum, tympanic membrane is considered the start of the middle ear.

The only ratios I have ever seen dealing with linked genes are 9:3:3:1 from a dihybrid cross, or a 1:1:1:1 from a hybrid x homozygous at both locus cross. If you see variation in the recombinant phenotypes then you can assume linkage occurred and you can calculate the recombinant freq.

I had that same question about Barr bodies, I never understood that part.
 

G1SG2

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What is the difference between gene drift and gene flow? I don’t understand why the Founder effect cannot be an example of either/or

What’s the difference between and ionophore and an ion channel?

Would the eardrum be considered a part of the outer or middle ear?

How do you know if a 1:2:1 ration in a punnett cross is caused by incomplete dominance or by linked genes?

If a barr body forms on a X chromosome that is wild type for a gene leaving a mutant gene on the uncondensed chromosome, would the woman would get the disease? If the answer is yes, then why do x-linked diseases affect men only?
Yeah, I never really understood what dictates the formation of the Barr body. Which X chromosome gets inactivated? Isn't it random?
 

Spiker

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What is the difference between gene drift and gene flow? I don't understand why the Founder effect cannot be an example of either/or

What's the difference between and ionophore and an ion channel?

Ionophore ususally is termed used to describe channel that dont ever close if i remember correctly

Would the eardrum be considered a part of the outer or middle ear?

How do you know if a 1:2:1 ration in a punnett cross is caused by incomplete dominance or by linked genes?

If a barr body forms on a X chromosome that is wild type for a gene leaving a mutant gene on the uncondensed chromosome, would the woman would get the disease? If the answer is yes, then why do x-linked diseases affect men only?

Yes the female will have the disease but only in half of the cells. bar body is not created after many divisions after fertilization so not all cells in 1 organ is affected so in the end they dont have the diease. for example haemophilia is cause by lack of clotting factor however if half of your organ can produce the clotting factor you are fine.
 

wanderer

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What is the difference between gene drift and gene flow? I don’t understand why the Founder effect cannot be an example of either/or
Genetic drift is when allele changes of a population change over time due to some random reason (i.e. not due to natural selection). The founder effect IS an example of genetic drift; it just means that if an entire population all descends from a small group, then that population's allele frequencies reflect the allele frequencies of its founders and not of the original population.

Gene flow is just the flow of genes between different populations.

You need to have a good grasp of the biological definition of populations.
 
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thebillsfan

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def of population=a community of organisms from the same species that can reproduce with each other?
 
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def of population=a community of organisms from the same species that can reproduce with each other?
I remember something saying

population's are reproducing with each other

species can reproduce with each other

so populations are a subset of species
 

wanderer

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def of population=a community of organisms from the same species that can reproduce with each other?
No, it's more like, "a community of organisms from the same species that typically reproduce with each other"
If it was exactly, "a community of organisms from the same species that can reproduce with each other" then the definition of gene flow wouldn't make as much sense.
Members of different populations can reproduce with each other as well.
I remember something saying

population's are reproducing with each other

species can reproduce with each other
Yea, this is what I'm getting at. Just keep in mind that members of different species can sometimes reproduce with each other; but there are a lot of very different definitions of the term species.
 

RogueUnicorn

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populations of a given species do not interbreed due to physical, geographical or other barrier; if said barrier were removed, they would interbreed.
 

capn jazz

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What’s the difference between and ionophore and an ion channel?

Ionophore ususally is termed used to describe channel that dont ever close if i remember correctly
This is wrong. An ionophore is a shuttle/carrier protein that can diffuse through the plasma membrane and carry ions across. An ionophore could come up on the MCAT in the context of an H+ shuttler that uncouples respiration from ATP synthesis.
 
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thebillsfan

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so ion channels are not just one type of ionophore? I understand the whole carrier diffusing thru the membrane thing, I just want to make sure that ion channels would not also be classified as ionophores since they have the same fxn
 

capn jazz

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so ion channels are not just one type of ionophore? I understand the whole carrier diffusing thru the membrane thing, I just want to make sure that ion channels would not also be classified as ionophores since they have the same fxn
Nope, an ion channel should pretty much live in the plasma membrane, either in an open, closed, or gated, or whatever form. An ionophore is mobile.
 
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Nope, an ion channel should pretty much live in the plasma membrane, either in an open, closed, or gated, or whatever form. An ionophore is mobile.
Any specifics about ionophores we should know besides that H+ example you stated?
 

capn jazz

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No, as long as you know what it is, I imagine any passage will tell you any details you need to know. Another biological example is that ionophores can be used in fertilization experiments to transport Ca2+ into the egg. Since Ca2+ is one of the triggers for forming the fertilization membrane (normally provided by the sperm), you can induce the fertilization reaction in an unfertilized egg by adding in a Ca2+ transporting ionophore to an egg.

You don't need to know ANY of that, it's just an example of a context in which an ionophore would be used: fertilization + cellular respiration