Chorion in terrestrial vertebrate embryos:
1. | prevents desiccation of the embryo |
2. | helps in the exchange of oxygen and carbon dioxide with the environment |
3. | perform excretory functions |
4. | acts as a shock absorber |
In humans, the majority of the placenta is formed by:
1. allantois
2. amnion
3. chorion
4. yolk sac
The functions of the placenta include:
I: | Acts as an excretory organ. |
II: | Acts as a respiratory organ. |
III: | Acts as an endocrine organ. |
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II, and III |
Human bones develop from embryonic:
1. ectoderm
2. endoderm
3. epiderm
4. mesoderm
Human lungs develop from embryonic:
1. ectoderm
2. endoderm
3. epiderm
4. mesoderm
During cleavage divisions, successive blastomeres:
1. have a decreasing nuclear/cytoplasmic ratio
2. become smaller and smaller
3. grow larger and larger
4. undergo meiotic divisions.
Human nervous system is derived from embryonic:
1. ectoderm
2. endoderm
3. epiderm
4. mesoderm
Gonadotropin releasing hormone (GnRH) is released from:
1. anterior pituitary
2. hypothalamus
3. gonads
4. posterior pituitary
Inhibin in males or females decrease the secretion of:
1. FSH
2. LH
3. GnRH
4. Sex steroids
Identify the correct statement regarding the onset of puberty amongst the following:
1. LH is the first hormone to demonstrate an increased secretion
2. GnRH secretion decreases
3. spermatogenesis in males in stopped
4. secretion of sex steroids decreases