By 80 years of age, about what percentage of muscle mass is lost?

Compared to 40 years ago, young people in the U.S. have premarital intercourse:

A) in higher numbers and earlier. B) in higher numbers, but later. C) in lower numbers and later. D) in lower numbers, but earlier.

Structures on the tongue that contain the receptor cells for taste are the ______

a. saccules c. hair cells b. golgi tendon organs d. taste buds