Changes that occur in boys only in adolescence are

The enlargement of the scrotum and testes.

Explanation:

Whelp here is your naswer since you asked

In boys, the initial puberty change is the enlargement of the scrotum and testes. At this point, the penis does not enlarge. Then, as the testes and scrotum continue to enlarge, the penis gets longer. Next, the penis will continue to grow in both size and length.

answer; a muscle cell, another neuron and a of the above

one characteristic that is shared by all is a soft body. many

of these invertebrate animals also have an outer shell to protect their

body. oysters, clams, snails, and mussels are all mollusks. so are octopuses, squids, and slugs. mollusks live on land and in freshwater.