With the implantation of the fertilized egg in the wall of the _______, cells in the egg grow into the fetal portion of a network of blood vessels and membranes that support the fetus. This is the _______.

Labor can be defined as regular _______ of uterine _______ that help bring about the birth of the baby.

Sperm begin development in the _______ and continue development and are stored in the convoluted tubules called the _______.

The material that is ejaculated from the penis, _______, is composed of both _______ and fluids secreted by three supporting _______.

Males are able to remain fertile throughout their lives because the cells called spermatogonia are reproductive _______ that give rise to more of themselves and to the _______ that develop into sperm.

While they are in development, the reproductive cells a woman produces are known as _______ and are produced in the organs called _______.

Every 28 days, on average, one of these reproductive cells is released in the process called _______ and then begins a journey down one of the woman’s _______.

Menstruation, the release of blood and a portion of the uterine tissue called the _______, occurs when there has been no _____ during the reproductive cycle.

When a couple is having trouble conceiving a child, the first thing fertility specialists generally will look at is the fertility of the prospective father. What do you think a specialist would be looking for?

The precursors of the eggs produced by females are (select all that apply):

a. released from ovaries.

b. released at the rate of about six per month.

c. called oocytes.

d. surrounded by fluids and accessory cells.

e. put into blood circulation.

Most mammals are “placental,” which is to say their embryos get nourishment within the mother through the placental system of blood vessels reviewed in the text. By contrast, amphibian and reptilian embryos are nourished by substances contained in eggs the mother lays. Can you think of any advantages mammals derive from the placental means of development? Can you think of any disadvantages?