Exam 28: Pregnancy and Human Development

At which stage of labor is the "afterbirth" expelled?

The formation of endodermal and ectodermal germ layers occurs at .

When do we begin to call the developing individual a fetus rather than an embryo?

Of the three germ layers, the mesoderm forms the most body parts.

How long is the egg viable and capable of being fertilized after it is ovulated?

A premature separation of the placenta from the uterine wall is called .

Mrs. Phang, eight months pregnant with her first child, makes an appointment with her obstetrician to investigate the cause of vaginal bleeding. Because it is actually more "spotting" than frank bleeding, and painless, she is becoming worried. Ultrasound visualization of her abdomen shows that the placenta is formed across the internal os of the cervix, and she is ordered to her bed for the remainder of the pregnancy. What name is given to Mrs. Phang's condition? Why is it an extremely serious condition? Why was she ordered to have complete bed rest for the remainder of her pregnancy?

Explain what triggers a baby's first breath.

Relaxin is a hormone produced by the placenta and ovaries. The function of this hormone is to )

As the newborn suckles, the mother's pituitary produces to assist in producing milk.

It is impossible for sperm to be functional (able to fertilize the egg) until after .

The trophoblast is mostly responsible for forming the .

Shortly after implantation .

The body systems of the developing embryo are present in at least rudimentary form at eight weeks.

The first axial support for the embryo is called the .

Which hormone is not produced by the placenta?

By 72 hours after fertilization, the egg has divided into more than 160 cells and is called the morula.

Figure 28.1Using Figure 28.1, match the following: -Trachea.

Figure 28.2Using Figure 28.2, match the following: -The part of the endometrium destined to be a part of the placenta.

Sperm move to the uterine tube through uterine contractions and the energy of their own flagella. What other factor is involved in sperm movement?