Sperm-producing cells have unique antigens yet they are not attacked by the immune cells because of:

1.	antigens are recognized as self-antigens.
2.	acrosome at the tip.
3.	protection by the blood-testis barrier.
4.	inhibitors attached on the surface.

Spermatic cord does not include:

1. testicular artery.

2. lymphatic vessels.

3. ductus deferens.

4. ejaculatory duct.

Cryptorchidism may lead to sterility due to:

1. relatively high internal body temperature.

2. excessive production of estrogen.

3. lack of testosterone.

4. non-function of the SRY gene.

In males, the secondary sexual characters develop in response to:
1. ICSH
2. FSH
3. testosterone
4. gonadotropin-releasing hormone

In males, FSH:

1. inhibits progesterone.

2. initiates testosterone production.

3. increases protein synthesis.

4. increase spermatogenesis.

The Papanicolaou test [PAP smear] is a method of screening used to detect potentially pre-cancerous and cancerous processes in the

1. urethra.

2. ovary.

3. cervix.

4. ovaries.

Menstrual irregularities may be seen in women athletes due to:

The endometrium is maintained in a healthy condition in the latter half of the pregnancy by:

1. FSH and LH

2. human chorionic gonadotropin

3. Ovarian steroids

4. placental estrogen and progesterone

The endometrium is the most developed:

1. during the menstrual phase.

2. just after the menstrual phase.

3. just after ovulation.

4. late in the postovulatory phase.

What happens to the corpus luteum if fertilization does not take place?