Changes in GnRH pulse frequency in females is controlled by circulating levels of :
1. | estrogen and inhibin | 2. | progesterone only |
3. | progesterone and inhibin | 4. | estrogen and progesterone |
The simultaneously occurring events during the menstrual cycle are:
1. | peak of LH secretion and menstrual flow |
2. | follicular development and the uterus becoming highly secretory |
3. | formation of corpus Albicans and an increase in progesterone secretion |
4. | Proliferation stage of the uterus and increased estrogen production |
Identify the correct statement regarding menopause:
1. | Follicles become less responsive to FSH and LH. |
2. | Elevated estrogen levels is the cause. |
3. | Marks the beginning of menstrual cycles. |
4. | Results when follicles develop but contain no oocytes. |
An organelle covering the head of animal sperm and containing enzymes that digest the egg cell coating, thus permitting the sperm to enter the egg is called as:
1. | nebenkern | 2. | manchette |
3. | head | 4. | acrosome |
Which endometrial stage corresponds to the follicular phase of the menstrual cycle?
1. | proliferative | 2. | luteal |
3. | secretory | 4. | menstruation |
The thick transparent glycoprotein membrane surrounding a mammalian ovum before implantation is called:
1. | oolemma | 2. | corona radiata |
3. | zona pellucida | 4. | cumulus oophorus |
The formation of the three embryonic germ layers is called:
1. | morulation | 2. | blastulation |
3. | neurulation | 4. | gastrulation |
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 |
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 |
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.