Answer:
1. Klinefelter syndrome
2. Nobody can be born with a single X chromosome
Explanation:
1. A genetic condition in which a male is born with an extra copy of the X chromosome
Klinefelter's syndrome isn't inherited, but rather occurs only as a result of a random genetic error after conception.
Males born with Klinefelter's syndrome may have low testosterone and reduced muscle mass, facial hair and body hair. Most males with this condition produce little or no sperm,
2. Sex chromosome occurs due to combination of the X and Y chromosome of both parents.
Answer:
Explanation:
From the question, the total population = 171 i.e (80+71+21)
Genetic frequency therefore; BB = 71/171 = 0.42
Bb = 80/171 = 0.47
bb = 20/171 = 0.12
Allele frequency therefore;
Allele B = 0.42+(0.50×0.47) = 0.66
Allele b = (0.50×0.47)+0.12 = 0.36
Note all values were rounded up to two significant figures
The oldest layers are on the bottom, and the youngest layers are on the top.