Down syndrome is
A. a sex-linked trait.
B. a recessive trait.
C. the result of having too few chromosomes.
D. the result of having an extra chromosome.
1 answer
D. the result of having an extra chromosome.
A. a sex-linked trait.
B. a recessive trait.
C. the result of having too few chromosomes.
D. the result of having an extra chromosome.
1 answer