Jeff is 13 years old and he has recently noticed some remarkable changes in himself.Over the past few months his voice has started to change,growing deeper.He has begun to grow pubic hair,as well as the beginnings of a facial beard.He is also filling out,with his muscles developing rapidly.These changes in Jeff are probably due to the action of _____________.
A)gonads
B)thyroid gland
C)pineal gland
D)adrenal gland

Question

Quizplus · Accepted Answer

These changes in Jeff are likely due to the action of his gonads, specifically his testes. During puberty, the testes begin to produce larger amounts of testosterone, which leads to the physical changes that Jeff is experiencing. The thyroid gland, pineal gland, and adrenal gland also play important roles in the body, but they are not directly responsible for the changes Jeff is experiencing.

Jeff Is 13 Years Old and He Has Recently Noticed