11.4 production of gametes

1. 11.4 Production of Gametes
Topic 11 Human Health & Physiology

2. Spermatogenesis
11.4.1 Annotate a light micrograph of testis tissue to show
the location and function of interstitial cells (Leydig cells),
germinal epithelium cells, developing spermatozoa and
Sertoli cells.
11.4.2 Outline the processes involved in spermatogenesis
within the testis, including mitosis, cell growth, the two
divisions of meiosis and cell differentiation.
(The names of the intermediate stages in spermatogenesis are
not required.)
11.4.3 State the role of LH, testosterone and FSH in
spermatogenesis.

3. Oogenesis
11.4.4 Annotate a diagram of the ovary to show the
location and function of germinal epithelium, primary
follicles, mature follicle and secondary oocyte.
11.4.5 Outline the processes involved in oogenesis within
the ovary, including mitosis, cell growth, the two
divisions of meiosis, the unequal division of cytoplasm
and the degeneration of polar body.
(The terms oogonia and primary oocyte are not required.)

4. Gametogenesis
11.4.6 Draw and label a diagram of a mature sperm and
egg.
11.4.7 Outline the role of the epididymis, seminal vesicle
and prostate gland in the production of semen.
11.4.8 Compare the processes of spermatogenesis and
oogenesis, including the number of gametes and the timing
of the formation and release of gametes.

5. Structure of the
Testis
Ref: Biology for the IB Diploma, Allott

6. Spermatogenesis
Ref: Biology for the IB Diploma, Allott

7. Summary of
Spermatogenesis
Ref: Biology for the IB Diploma, Allott

8. Hormonal control of
Spermatogenesis
Three hormones are involved in the production of sperm.
FSH (Follicle Stimulating Hormone).
Produced in the pituitary gland (brain).
Stimulated primary spermatocytes to undergo the first meiotic
division to form secondary spermatocytes.
Testosterone.
Produced in the interstitial cells in the testies
Stimulates the development of secondary spermatocytes into
mature sperm.
LH (Lutenising Hormone) - (ICSH will not be used)
Produced in the pituitary gland (brain).
Stimulates the secretion of testosterone by the testis

9. Production of Semen
Three structures help to produce semen:
The epididymis.
Sperm arrive here unable to swim.
The sperm mature while they are stored in the epididymis and learn
to swim.
Seminal vesicles.
Produces fluid which contains nutrients for the sperm (fructose).
Also contains mucus which protects the sperm in the vagina.
Prostate gland.
Produces a fluid which contains mineral ions.
The fluid is also alkaline to protect the sperm in the acidic
conditions of the vagina.

10. Structure of Mature Sperm
Ref: Biology for the IB Diploma, Allott
Ref: Yr11 Biology, Biozone

11. Structure of the Ovaries
Ref: Biology for the IB Diploma, Allott

12. Oogenesis
Ref: Biology for the IB Diploma, Allott

13. Summary of
Oogenesis
Ref: Biology for the IB Diploma, Allott

14. Structure of a Mature Egg

15. Spermatogenesis and Oogenesis
Compared
Spermatogenesis
Millions produced daily
Released during ejaculation.
Sperm formation starts during
puberty in boys.
Sperm production continues
throughout the adult life of
men.
Four sperm produced per
meiosis.
Oogenesis
One matures every 28 days
Released on about day 14 of
menstrual cycle by ovulation.
The early stages of egg
production happen during fetal
development in females.
Egg production becomes
irregular and then stops at
menopause in women.
Only one egg is produced per
meiosis.

16. IBO guide:
11.4.1 Annotate a light micrograph of testis tissue to show
the location and function of interstitial cells (Leydig cells),
germinal epithelium cells, developing spermatozoa and
Sertoli cells.
11.4.2 Outline the processes involved in spermatogenesis
within the testis, including mitosis, cell growth, the two
divisions of meiosis and cell differentiation.
(The names of the intermediate stages in spermatogenesis are
not required.)
11.4.3 State the role of LH, testosterone and FSH in
spermatogenesis.

17. IBO guide:
11.4.4 Annotate a diagram of the ovary to show the
location and function of germinal epithelium, primary
follicles, mature follicle and secondary oocyte.
11.4.5 Outline the processes involved in oogenesis within
the ovary, including mitosis, cell growth, the two
divisions of meiosis, the unequal division of cytoplasm
and the degeneration of polar body.
(The terms oogonia and primary oocyte are not required.)

18. IBO guide:
11.4.6 Draw and label a diagram of a mature sperm and
egg.
11.4.7 Outline the role of the epididymis, seminal vesicle
and prostate gland in the production of semen.
11.4.8 Compare the processes of spermatogenesis and
oogenesis, including the number of gametes and the timing
of the formation and release of gametes.