IC4

Question 1

ovarian cycle general

Answer 1

• 2 alternating phases
• 28 day cycle
• interrupted by pregnancy
• terminated by menopause

Question 2

ovarian cycle phase - follicular phase - general

Answer 2

• dominated by presence of maturing follicles
• start at puberty (hypothalamus increase GnRH production)

Question 3

ovarian cycle phase - follicular phase - action of GnRH

Answer 3

• stimulate anterior pituitary gland to secrete LH & FSH for synthesis & secretion of estrogen by follicular cell

Question 4

ovarian cycle phase - follicular phase - action of FSH

Answer 4

1) aid follicle growth & maturation
2) induce antrum formation (liquid space, store estrogen)

Question 5

ovarian cycle phase - follicular phase - negative feedback

Answer 5

• in response to moderate level of estrogen
• hypothalamus inhibit GnRH secretion
• anterior pituitary inhibit FSH secretion
• follicular cell secrete inhibin -> inhibit FSH secretion
• LH continue to rise slowly -> increase in estrogen + maturation of follicle

Question 6

ovarian cycle phase - follicular phase - positive feedback

Answer 6

• in response to high levels of estrogen
• act on hypothalamus & pituitary gland -> increase GnRH & selectively stimulate LH secretion -> surge in LH secretion -> differentiation of follicular cell into luteal cell + ovulation occur
• follicular cell secrete inhibin -> selectively inhibit FSH

Question 7

ovarian cycle phases - luteal phase - identifying feature

Answer 7

presence of corpus luteum

Question 8

ovarian cycle phases - luteal phase - what happens when fertilisation occurs

Answer 8

under the presence of LH, corpus luteum secretes:
1) estrogen
2) progesterone
- inhibit LH & FSH to prevent maturation of new follicle & ovulation

Question 9

ovarian cycle phases - luteal phase - what happens when no fertilisation occurs

Answer 9

corpus luteum degenerate -> X estrogen/progesterone produced -> inhibit negative feedback -> new follicular phase

Question 10

uterine cycle (menstrual cycle) - significance

Answer 10

1) reflect cyclic changes of female sex hormone during ovarian cycle
2) prepare female reproductive tract for fertilisation & implantation of ovum

Question 11

uterine cycle (menstrual cycle) - endometrial changes

Answer 11

1) start of follicular phase: menses
- destruction of functional zone

2) end of follicular phase: proliferative phase
- repair & regeneration of functional zone

3) luteal phase: secretory phase
- secretion of endometrial glands

Question 12

what is female puberty triggered by

Answer 12

GnRH released at puberty

Question 13

what are the signs of female puberty

Answer 13

1) thelarche: earliest, develop breast
2) pubarche: growth of pubic & axillary hair
3) menarche: first menstrual period
4) growth of secondary sex organs
5) fat deposition
6) rapid increase in height

Question 14

why does low body weight delay puberty in girls?

Answer 14

low body weight = lesser fat distribution = lower production of hormones (steroid moiety)

Question 15

signs of menopause

Answer 15

1) X menstrual cycle
2) Atrophy of genital organs
3) vasomotor change
4) skin, emotional, psychological change
5) increase cholesterol level
6) increase risk of osteoporosis

Question 16

menstrual disorders

Answer 16

1) amenorrhea (lack bleeding)
2) dysmenorrhea (pain)
3) menorrhagia (excess blood)
4) metrorrhagia (irregular blood)