Serpwidgets
New member
For those who might enjoy it, I've made up a quiz on genetics and inheritance. If you have a decent grasp of the material in my genetics/inheritance tutorial, you should be able to answer most of these, and deduce the answers to the rest of them.
I'll give out the answers/explanations on Sunday for anyone who wants to check their work.
If you have questions or need clarification/re-explanation of any of the questions, ask away.
Note: unless otherwise mentioned,
Basic:
Define Heterozygous and Homozygous.
What is the difference between Phenotype and Genotype?
What is the difference between Dominant, Codominant, and Recessive?
What are the possible genotypes for a simple trait called A?
If a trait is recessive, what is the genotype of an animal that expresses this trait?
If a trait is dominant, what is the genotype of an animal that expresses this trait?
If a trait is codominant, how many phenotypes exist for the possible genotypes?
If an animal is het for a recessive trait, what does it look like?
If you breed "A" (an A-mutant, which shows that trait) X "het for A" what will the offspring look like?
Intermediate:
Define Allele.
Define Locus.
When both parents are het for the same recessive trait, what is the best description of their normal-looking offsprings' genotype?
What do P, F1, F2 mean?
When both parents are "double-het for A and B,"
If an animal has never been bred but is known to be het for trait A, what can be said about its parents?
Where A is recessive and D is a dominant trait: breeding "A het for D" X "het for A" will give you what results?
Given that 3 alleles exist for trait A:
How many possible phenotypes are there?
If you breed "22" X "33":
Advanced:
What are the advantages and disadvantages of inbreeding?
You find a wild amelanistic male, bring it home, and breed it to a never-been-bred amelanistic female in your collection. All of the offspring are normal. Explain.
While in the 5th generation of line-breeding normal cornsnakes, you mate 4 brother/sister pairs. Every clutch results in 20 hatchlings. In all but one clutch, the offspring are all normal, as you would expect. Out of 20 of the hatchlings in the other clutch, 5 of them show a new (never-before-seen) trait.
A new recessive allele appears in a wild population. When expressed, this trait makes survival in the wild impossible. At what point does being heterozygous for this trait create a selection disadvantage?
I'll give out the answers/explanations on Sunday for anyone who wants to check their work.
If you have questions or need clarification/re-explanation of any of the questions, ask away. Note: unless otherwise mentioned,
- all mutations/traits are recessive to "normal,"
- all mutations only have one wild-type and one mutant allele,
- and all mutations are inherited in simple fashion.
Basic:
Define Heterozygous and Homozygous.
What is the difference between Phenotype and Genotype?
What is the difference between Dominant, Codominant, and Recessive?
What are the possible genotypes for a simple trait called A?
If a trait is recessive, what is the genotype of an animal that expresses this trait?
If a trait is dominant, what is the genotype of an animal that expresses this trait?
If a trait is codominant, how many phenotypes exist for the possible genotypes?
If an animal is het for a recessive trait, what does it look like?
If you breed "A" (an A-mutant, which shows that trait) X "het for A" what will the offspring look like?
Intermediate:
Define Allele.
Define Locus.
When both parents are het for the same recessive trait, what is the best description of their normal-looking offsprings' genotype?
What do P, F1, F2 mean?
When both parents are "double-het for A and B,"
- What is the expected ratio of phenotypes in the offspring?
- How would you describe the genotypes of the offspring that only express mutation B?
If an animal has never been bred but is known to be het for trait A, what can be said about its parents?
Where A is recessive and D is a dominant trait: breeding "A het for D" X "het for A" will give you what results?
Given that 3 alleles exist for trait A:
- A1 (dominant wild-type),
- A2 and A3 (recessive to A1, and codominant to each other)
How many possible phenotypes are there?
If you breed "22" X "33":
- What will the offspring look like?
- Are the offspring homozygous or heterozygous?
Advanced:
What are the advantages and disadvantages of inbreeding?
You find a wild amelanistic male, bring it home, and breed it to a never-been-bred amelanistic female in your collection. All of the offspring are normal. Explain.
While in the 5th generation of line-breeding normal cornsnakes, you mate 4 brother/sister pairs. Every clutch results in 20 hatchlings. In all but one clutch, the offspring are all normal, as you would expect. Out of 20 of the hatchlings in the other clutch, 5 of them show a new (never-before-seen) trait.
- What is most likely to have happened?
- What is the most likely mode of inheritance of this trait? (simple/complex, dominant/codominant/recessive?)
- Where would you suspect the trait to have originated?
- Statistically, how many of the 80 offspring would be het for this new trait?
A new recessive allele appears in a wild population. When expressed, this trait makes survival in the wild impossible. At what point does being heterozygous for this trait create a selection disadvantage?
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