Question
Question: a. How is ‘oogenesis’ markedly different from ‘spermatogenesis ‘with respect to the growth till pube...
a. How is ‘oogenesis’ markedly different from ‘spermatogenesis ‘with respect to the growth till puberty in humans ?
b. Draw a sectional view of the human ovary and label the different follicular stages , ovum and corpus luteum.
Solution
Hint:- Gametogenesis is the process of the formation of gametes by the primary sex organs. Male gametes are called sperms and are produced by a process called spermatogenesis. In females, mature female gametes are formed by a process called oogenesis. Production of sperms by spermatogenesis only begins at the puberty stage while oogenesis begins at the embryonic developmental stage itself.
Complete solution:
a)
Spermatogenesis | Oogenesis |
---|---|
Takes place in the testis and starts only in puberty. | Takes place in the ovary and starts in the embryonic development stage itself. |
The first and second meiotic divisions of the spermatogonium take place within the seminiferous tubules itself. | The first meiotic division takes place in the follicles of the ovary before ovulation and the second meiotic division takes place outside the ovaries after ovulation. |
Each primary spermatocyte gives rise to four viable haploid spermatids after second meiotic division | Each primary oocyte gives rise only to one haploid fertilizable ovum and two non-functional polar bodies after the second meiotic division. |
Spermatids are transformed into sperms and undergo spermiation and are finally released for fertilization. | The secondary oocytes or ovum are released during ovulation and can fertilize. |
b)
Note:- The process of spermatogenesis and release of sperms usually continues till the death of a human male once it starts at puberty. But the process of oogenesis and ovulation ceases at an age of 50 – 55 in human females. The menstrual cycle is the reproductive cycle seen in females of humans and other primates. Ovum is usually released once in 28 days. Menarche is the first menstruation and menopause is the end of the menstrual cycle.