The gonads, or primary sex organs, produce sex cells, also known as ________

The repeating unit of a skeletal muscle fiber is the

A) sarcolemma. B) sarcomere. C) sarcoplasmic reticulum. D) myofibril. E) myofilament.

Sperm cells develop in the:

a. interstitial cells b. tunic albuginea c. prostate gland d. seminiferous tubules

Located throughout the layers of the muscularis externa are pacemaker cells known as the ______

Fill in the blank(s) with correct word

Which of these molecules is hydrophobic?

A) Amino acid B) Protein C) Glucose D) Disaccharide E) Cholesterol