Class 12th Biology 2011 Set1 Delhi Board Paper Solution
Question 28
(a) Draw a labelled diagram of the human female reproductive system.
(a) Draw a labelled diagram of the human female reproductive system.
(b) Enumerate the events in the ovary of a human female during:
I. Follicular phase
II. Luteal phase of menstrual cycle
OR
(a) Write the specific location and the functions of the following cells in human males:
I. Leydig cells
II. Sertoli cells
III. Primary spermatocyte
(b) Explain the role of any two accessory glands in human male reproductive system.
Answer
(a)
(b)
I. Menstruation phase is followed by follicular phase, primary follicle grow and became graafian follicle and stimulate endometrium of uterus regenerates through proliferation. Change in ovary and uterus cause change in hormone level such as LH and FSH. LH and FSH attains maximum level on about 14th day of menstruation, and initiate rupture of graafian follicle and thereby the release of ovum (ovulation).
II. Ovulatory phase is followed by luteal phase, at this time remaining amount of graafian follicle gets converted into corpus luteum, It induces secretion of progesterone which maintains endometrium. Endometrium is important in implementation of fertilised ovum. At the time of pregnancy events of menstrual cycle stop.
OR
(a)
I. Location- they are located in the loose connective tissues surrounding seminiferous tubules, rich in cholesterol content.
Function – they are actively involved in the production of testosterone and formation
of other hormone.
II. Location - Sertolic cells are present at the seminiferous tubules. The male germ cells
Function - they provide nutrition to the germ cells, lying outside seminiferous tubules.
III. Location – spermatogonia present on the innere side of the seminiferous tubule undergo mitosis to form diploid spermatogonium.
Function – this primary spermatogonium undergo first mitotic reduction division forming two equal haploid cells called secondary spermatocyte.
(b) Two male accessory glands in human male include paired seminal vesicles, prostate and paired bulbourethral glands. Secreted components from these glands are rich in fructose, calcium and certain enzymes. Secretion of bulbourethral gland helps to lubricate penis.
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