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Human Reproduction — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Reproduction5 Marks
Question
Write two differences between spermatogenesis and oogenesis.
✓

Answer

S. No. Spermatogenesis Oogenesis
(i)
It is the process of formation of haploid spermatozoa from diploid male germ cells of the testes.
It is the process of formation of haploid ova from the gamete mother cells (oogonia) in the ovary.
(ii)
It occurs in testes.
It occurs in ovaries.
(iii)
A primary spermatocyte divides to form two secondary spermatocytes by meiosis I.
A primary oocyte divides by meiosis I to form one secondary oocyte and a polar body.
(iv)
Spermatogonia changes to primary spermatocyte.
Oogonia changes to primary oocyte.
(v)
A secondary spermatocyte divides to form two spermatids by meiosis II.
A secondary oocyte divides by meiosis II to form ovum and a polar body.
(vi)
No polar body is formed.
Polar bodies are formed.
(vii)
Four spermatozoa are produced from one primary spermatocyte.
One ovum/ egg is produced from one primary oocyte.

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