Class 12 Biology - Chapter Human Reproduction NCERT Solutions | What is oogenesis? Give a brief account
Welcome to the NCERT Solutions for Class 12th Biology - Chapter Human Reproduction. This page offers a step-by-step solution to the specific question from Excercise 1 , Question 12: what is oogenesis give a brief account of oogenes....
Question 12
What is oogenesis? Give a brief account of oogenesis.
Answer
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
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- 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)
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10 Comment(s) on this Question
Mansoon
2020-07-19 09:58:19
Thanks for helping me
M J N
2019-10-22 10:56:31
Very very nice answer
Priya
2019-09-11 18:29:08
Thanks ð
lllll
2019-02-26 19:41:13
6
Atul Pandey pandya
2019-02-23 19:06:57
Nice answer guru jii Atul pandya
Zephaniah dominic
2019-02-16 05:24:52
Excellent answer....thank you very much.....
shanu kumar
2019-01-28 21:52:35
many many thanks mast answer hai
Vishal kumar
2019-01-22 15:35:38
Best answer
Kirti
2019-01-12 15:27:24
Very nice answer
JUDHISTHIRA
2018-08-26 19:11:19
Excellent answer
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