Assignment 16

Answer any four of the questions. This assignment is for extra credit and is due at the last class period.

1. One of the more common congenital cardiac disorders is a ventricular septum defect in which an opening remains between the left and right ventricles. What problem would such a defect create as blood moves through the heart after the birth of the infant. What symptoms may appear in a newborn if its ductus arteriosus fails to close?

2. Describe the stages of fertilization. What is happening to the sperm and the ovum? Where in the female reproductive system does fertilization occur?

3. Describe the prenatal stages from fertilization to, and including, implantation. Describe the role of hCG during the period of cleavage.

4. Develop a table that summarizes the major structures derived from the three major germ layers.

5. Describe the structure of the placental membrane and diffusion of gases across the membrane. Explain the maternal and embryonic portions of the placenta. Discuss the formation of the umbilical cord. What endocrine functions does the placenta facilitate?

6. Discuss environmental factors that may cause malformation in the developing embryo and fetus.