Suppose that a child developed mild symptoms of sickle-cell anemia

Suppose that a child developed mild symptoms of sickle-cell anemia. It may be correctly inferred that
a.   the child is heterozygous for the sickle-cell trait.
b.   the child received the sickle-cell trait from both parents and is homozygous for this disorder.
c.   the sickle trait is absent from the child’s alleles.
d.   the symptoms developed from experiential learning.

Sex-linked genetic characteristics appear in phenotypes
a.   of women more often than men.
b.   of men more often than women.
c.   of women and men rarely and equally.
d.   of women and men often and equally.


When chromosomal abnormalities occur,
a.   most are fatal, killing the baby and pregnant mother.
b.   most result in miscarriage early in the pregnancy.
c.   most of the defective offspring survive birth, but die during infancy.
d.   the chromosomal defects can later be repaired surgically during infancy.