The epidermis and the dermis of the skin develops respectively from embryonic:
1. ectoderm, endoderm
2. ectoderm, mesoderm
3. endoderm, mesoderm
4. endoderm, ectoderm

Identify the organ system in humans that is derived from all the three embryonic germ layers:
1. cardiovascular system.
2. digestive system.
3. endocrine system.
4. muscular system.

Lactation after child birth is possible due to decrease in the secretion of:
1. HCG
2. oxytocin
3. FSH and LH
4. estrogen and progesterone

The initial phase of the cortical reaction leads to:
1. slow block to polyspermy
2. fast block to polyspermy
3. formation of pronuclei
4. completion of acrosome reaction

Identify the incorrect statement:
1. Spermatogenesis begins at puberty.
2. Secondary spermatocyte has 23 chromosomes.
3. Oogenesis lasts only from puberty until menopause
4. oogenesis begins in fetal life

Identify the incorrect statement:

The testes of a pre-pubertal boy will have:
1. spermatocytes
2. spermatozoa
3. spermatogonia
4. spermatid

The dilated end of vas deferens are called:
1. corpus
2. seminal vesicle
3. ampulla
4. tubuli recti

Human embryos will develop into female by default due to:
1. presence of an X chromosome
2. an ovarian determining factor
3. presence of a Y chromosome
4. lacks of Y sex chromosome

Labor can be hastened by:
1. progesterone
2. estradiol
3. prostaglandins
4. HCG