Class 12 Biology - Chapter Human Reproduction NCERT Solutions | How many eggs are released by a human ov
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 Exercise 1, Question 20: how many eggs are released by a human ovary in a m....
Question 20
How many eggs are released by a human ovary in a month?
How many eggs are released by a human ovary in a month?
How many eggs do you think would have been released if the mother gave birth to identical twins?
Would your answer change if the twins born were fraternal?
Answer
An ovary releases an egg every month. When two babies are produced in succession, they are called twins. Generally, twins are produced from a single egg by the separation of early blastomeres resulting from the first zygotic cleavage. As a result, the young ones formed will have the same genetic make- up and are thus, called identical twins.
If the twins born are fraternal, then they would have developed from two separate eggs. This happens when two eggs (one from each ovary) are released at the same time and get fertilized by two separate sperms. Hence, the young ones developed will have separate genes and are therefore, called non-identical or fraternal twins.
More Questions From Class 12 Biology - Chapter Human Reproduction
- Q:- What is spermatogenesis? Briefly describe the process of spermatogenesis.
- Q:- What is oogenesis? Give a brief account of oogenesis.
- 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.
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2 Comment(s) on this Question
Supriya
2019-04-10 19:56:22
Nice answer for exam preparation
Aynal Hoque
2018-10-23 10:27:17
Mozzza...
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