Which structure found in eukaryotes has a single membrane?

A. Nucleus

B. Lysosome

C. Chloroplast

D. Mitochondrion

B

What is a similarity between the testes of males and the ovaries of females in humans?

A. They produce gametes throughout the life of the individual.

B. They secrete hormones into the blood stream.

C. Their development is controlled by a gene on the Y chromosome.

D. They release products to the outside of the body directly through the urethra.

B

What is the function of the hormone leptin?

A. Increase the uptake of glucose from the blood

B. Reduce appetite

C. Increase metabolic rate

D. Promote sleep

B