Down syndrome results from a chromosomal abnormality where there is an extra 21st chromosome.

1 point
a.

monosomy

b.

trisomy

c.

mitotic

d.

replication

need

Internal feedback works to maintain homeostasis when your a. heart rate decreases as your white blood cells increase b. breathing rate decreases as your red blood cells decrease c. heart rate increases as your liver is cleaning blood d. breathing rate increases as your heart rate increases