Class 12 Biology - Chapter Human Reproduction NCERT Solutions | What is oogenesis? Give a brief account
What is oogenesis? Give a brief account of oogenesis.
Oogenesis is the process of the formation of a mature ovum from the oogonia in females. It takes place in the ovaries. During oogenesis, a diploid oogonium or egg mother cell increases in size and gets transformed into a diploid primary oocyte. This diploid primary oocyte undergoes first meiotic division i.e., meiosis I or reductional division to form two unequal haploid cells. The smaller cell is known as the first polar body, while the larger cell is known as the secondary oocyte. This secondary oocyte undergoes second meiotic division i.e., meiosis II or equational division and gives rise to a second polar body and an ovum. Hence, in the process of oogenesis, a diploid oogonium produces a single haploid ovum while two or three polar bodies are produced.
More Questions From Class 12 Biology - Chapter Human Reproduction
- Q:- What is spermatogenesis? Briefly describe the process of spermatogenesis.
- Q:- Describe the structure of a seminiferous tubule.
- Q:- Identify True/False statements. Correct each false statement to make it true.
(a) Androgens are produced by Sertoli cells. (True/False)
(b) Spermatozoa get nutrition from Sertoli cells. (True/False)
(c) Leydig cells are found in ovary. (True/False)
(d) Leydig cells synthesise androgens. (True/False)
(e) Oogenesis takes place in corpus luteum. (True/False)
(f) Menstrual cycle ceases during pregnancy. (True/False)
(g) Presence or absence of hymen is not a reliable indicator of virginity or sexual experience. (True/False) - Q:- What are the major components of seminal plasma?
- Q:- Write two major functions each of testis and ovary.
- Q:-
What is menstrual cycle? Which hormones regulate menstrual cycle?
- Q:- What are the major functions of male accessory ducts and glands?
- Q:- Name the functions of the following.
(a) Corpus luteum
(b) Endometrium
(c) Acrosome
(d) Sperm tail
(e) Fimbriae - Q:- Name the hormones involved in regulation of spermatogenesis.
- Q:- Define spermiogenesis and spermiation.
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