CH15

Question 1

6 Structure of male reproductive system

Answer 1

Testis
- secretes testosterone
- produces sperm

Sperm duct
- direct sperm from testis

scrotum
- protect testis

seminal vesicle
- secrete fluid and nutrient for sperm

Prostate gland
- secrete fluid to facilitate movement of sperm

urethra
- direct urine and sperm out of the body

Question 2

Process of Spermatogenesis

Answer 2

Primordial germ cell (2n) -Mitosis-> Spermatogonium (2n) -Cell growth-> Primary Spermatocyte (2n) -meiosis 1-> Secondary Spermatocyte (n) -meiosis 2-> spermatid -cell differentiation-> sperm

Question 3

Process of Oogenesis

Answer 3

Before birth:
- primordial germ cell 2n undergoes Mitosis to produce oogonium 2n
- Oogonium 2n undergoes mitosis to produce primary oocytes
- Primary oocytes 2n undergoes meiosis i but stops prophase i
- Each primary oocyte is surrounded by a layer of follicle cells that provide nutrient and secrete oestrogen

After birth
- Baby girl has millions of primary oocyte 2n
- Primary oocytes is dormant until she reaches puberty

After Puberty
- Primary oocytes 2n complete meiosis 1 to form secondary oocytes and 1 first polar body
- Secondary oocytes n undergoes meiosis ii and stops at metaphase ii
- Secondary oocytes is surrounded by secondary follicle that develops into graafian follicle and secretes oestrogen
- During ovulation, matured graafian follicle moves toward ovary and releases secondary oocytes into fallopian tube

Question 5

4 Hormones involved in menstrual cycle

Answer 5

FSH
- stimulate development of follicle in ovary
- stimulate ovary to secrete oestrogen

LH
- stimulates ovulation
- stimulate ovary to secrete progesterone
- stimulate formation of corpus luteum

Oestrogen
- Stimulate pituitary gland to secrete FSH & LH before ovulation
- stimulate hypothalamus to secrete GnRH
- Stimulate thickening of endometrium
- stimulate development of follicle until maturity

Progesterone
- Stimulate thickening of endometrium and enrich it with blood vessel for embryo implantation
- Inhibit secretion of FSH (prevent development of follicle) and LH (prevent ovulation)

Question 6

Process of menstrual cycle

Answer 6

Week 1 (Secretion & FSH Function)
-GnRH stimulate pituitary gland to secrete FSH and LH into bloodstream
- FSH stimulate development of follicle in ovary
- Primary oocytes in primary follicle will develop into secondary oocytes in Graafian follicle
- Developing follicle secretes oestrogen that stimulate thickening of endometrium & development of follicle