Consider the given two statements:
I. Secretion of androgen-binding protein (ABP) by Sertoli cells is very important for effective spermatogenesis.
II. Testosterone is required in large local concentrations to maintain the process.
1. Both I and II are correct and II explains I.
2. Both I and II are correct but II does not explain I.
3. Only I is correct.
4. Both I and II are incorrect
Consider the given statements:
I. Primary oocyte begins meiosis I embryonic development, but gets arrested in the diplotene stage of prophase I until puberty.
II. Immediately after meiosis I, the haploid secondary oocyte initiates meiosis II but gets arrested at metaphase II stage until fertilization, if such should ever occur.
III. If the secondary oocyte is not fertilized it does not complete meiosis II and doesn't become an ovum.
1. Only I and II are correct
2. Only I and III are correct
3. Only II and III are correct
4. I, II and III are correct
The hypothalamus and the pituitary gland mainly control the menstrual cycle. A series of physiological and anatomical processes of puberty culminates in menarche. Which of the following is the most important causal reason for the onset of puberty?
1. | The release of pulses of GnRH by the hypothalamus |
2. | The release of gonadotropins by the anterior pituitary |
3. | Inhibition of GnRH due to increase in circulating gonadotropins |
4. | Secretion of estrogen by the ovaries in response to pituitary hormones |
The menstrual cycle in human females involves two cycles - the ovarian cycle and the uterine cycle. While the ovarian cycle describes changes that occur in the follicles of the ovary, the uterine cycle describes changes in the endometrial lining of the uterus. The term that will be descriptive of a phase in the ovarian cycle but not the uterine cycle is:
1. | Menstruation | 2. | Luteal phase |
3. | Proliferative phase | 4. | Secretory phase |
I: | stimulates primary spermatocytes to undergo the first division of meiosis, to form secondary spermatocytes. |
II: | enhances the production of androgen-binding protein by the Sertoli cells of the testes |
1. | Only I | 2. | Only II |
3. | Both I and II | 4. | Neither I nor II |
1. | Only I | 2. | Only II |
3. | Both I and II | 4. | Neither I nor II |
1. | Only I and II | 2. | Only I and III |
3. | Only II and III | 4. | I, II and III |
I: | The presence or absence of hymen is not a reliable indicator of virginity or sexual experience. |
II: | It is a membrane that often covers the opening of vagina partially. |
1. | Both I and II are correct and II explains I |
2. | Both I and II are correct and II does not explain I |
3. | I is correct and II is incorrect |
4. | Both I and II are incorrect |