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Genetics Questions

1. Draw all possible chromosome configurations in Metaphase I with a dihybrid AaBb.

2. Do the same things as in question 1 for the genotype AaBbCc.

3. How many types of gametes would result from a dihybrid AaBb? What are they?

4. What portion of the zygotes will be
a. AaBBCc?
b. AABBCc?
c. AaBbCc?

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1. Draw all possible chromosome configurations in Metaphase I with a dihybrid AaBb.

During Metaphase I of meiosis, chromosome pairs line up, then are separated during Anaphase I.

In an individual with the genotype AaBb, the chromosome configurations could either be AB ab or Ab aB. During Metaphase I, the chromosome pairs would look like:

A A a a OR A A a a
B B b b b b B B

(In my diagram, each box contains a chromosome, and each column of letters is a strand of chromatid. The chromosomes are usually drawn to look like X's at this stage, because the two chromatids are connected at the centromere.)

This would lead to daughter cells (at the end of meiosis I) with the genotypes AB and ab in the first case, and Ab and aB in the second case.

2. Do the same things as in question 1 for the genotype AaBbCc.

For the genotype, ...

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