If two primary spermatocytes and two primary oocytes undergo meiosis simultaneously, what will be the ratio of spermatozoa and ova produced at the end of gametogenesis?
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The difference in gamete production reflects the reproductive strategies of males and females.
- 2:1
- 4:1
- 6:2
- 1:2
The Correct Option is B
Approach Solution - 1
If two primary spermatocytes and two primary oocytes undergo meiosis, the spermatozoa:ova ratio will be 8:2 (simplified as 4:1).
(A) 2:1 - Incorrect: Underestimates sperm production (each spermatocyte yields 4 sperm).
(B) 4:1 - Correct: 2 spermatocytes → 8 sperm; 2 oocytes → 2 ova (plus polar bodies).
(C) 6:2 - Incorrect: Mathematically incorrect for the given inputs.
(D) 1:2 - Incorrect: Reverses the expected ratio.
The correct answer is (B) 4:1, reflecting spermatogenesis (4 sperm per spermatocyte) vs. oogenesis (1 ovum per oocyte).
Approach Solution -2
Spermatogenesis involves the division of a primary spermatocyte into four sperm cells. Oogenesis involves the division of a primary oocyte into only one functional ovum and three non-functional polar bodies.
Therefore, from two primary spermatocytes and two primary oocytes, we get 4 sperm cells and 1 ovum.
Option (B) is correct because the ratio of spermatozoa to ova is 4:1.
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