Answer:
37.5%
Explanation:
These here are
Black (AA or Aa) and albino (aa)
Agouti (Bb or BB)
Thus, a cross between
AaBb and aaBb
The percent of the progeny which are likely to be agouti would be
A. a. B. b
a. Aa. aa. B. BB. Bb
a. Aa. aa. b. Bb. bb
The probability of agouti would be
1/2 (Aa) * 3/4 (BB or Bb)
= 3/8
= 37.5%
Two genes, BRCA1, located on chromosome 17q21 (5,6), and BRCA2, located on 13q12-13 (7–9), have been shown to predispose to familial breast cancer.
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Chromosomes are not visible in the cell’s nucleus—not even under a microscope—when the cell is not dividing. However, the DNA that makes up chromosomes becomes more tightly packed during cell division and is then visible under a microscope. Most of what researchers know about chromosomes was learned by observing chromosomes during cell division.