unit 2.2: hormonal control of reproduction

Question 1

what are hormones

Answer 1

chemical messengers

Question 2

where are hormones produced

Answer 2

endocrine glands

Question 3

how are hormones secreted

Answer 3

into the bloodstream

Question 4

when hormones reach a __________ they __________

Answer 4

a target organ
bring about a specific effect

Question 5

when is puberty triggered

Answer 5

when the hypothalamus secretes a releaser hormone

Question 6

what does this releaser hormone target

Answer 6

the pituitary gland

Question 7

what are the 2 hormones produced in males by the pituitary

Answer 7

follicle stimulating hormone (FSH)
interstitial cell stimulating hormone (ICSH)

Question 8

what are the 2 hormones produced by the pituitary in females

Answer 8

FSH
lutenising hormone (LH)

Question 9

what does FSH do (males)

Answer 9

promotes sperm production in seminiferous tubules

Question 10

what does ICSH do (males)

Answer 10

stimulates interstitial cells to produce testosterone

Question 11

what does testosterone stimulate

Answer 11

also stimulates sperm production
activates seminal vesicles and prostate gland to secrete their fluids

Question 12

what is the control of hormones known as

Answer 12

negative feedback control

Question 13

give an example of negative feedback for hormones in males

Answer 13

as testosterone reaches a high level, it inhibits FSH and ICSH secretion, this leads to decrease in testosterone concentration and as a result pituitary released FSH and ICSH again

Question 14

how long is the menstrual cycle

Answer 14

28 days (approx)

Question 15

what is the first day marked by

Answer 15

menstruation (bleeding)

Question 16

what are the 2 phases of the menstrual cycle

Answer 16

follicular phase
luteal phase

Question 17

what happens between days 1-5 in the menstrual cycle

Answer 17

endometrium begins to repair

Question 18

what happens on day 14

Answer 18

ovulation

Question 19

what is the endometrium at day 14

Answer 19

thick and spongy

Question 20

what does FSH do (females)

Answer 20

stimulates development and maturation of a follicle in the ovaries

stimulates the wall of the follicle and ovarian tissue to secrete oestrogen

Question 21

what does oestrogen stimulate

Answer 21

proliferation (increased cell division)

Question 22

why does oestrogen stimulate proliferation

Answer 22

so the endometrium can be repaired in preparation for receiving implantation of an embryo

Question 23

what happens when oestrogen reaches a high level

Answer 23

inhibits secretion of FSH from pituitary and a surge of LH is stimulated

Question 24

what does the surge of LH cause

Answer 24

ovulation

Question 25

what is ovulation

Answer 25

release of an egg from a mature follicle

Question 26

what do high oestrogen levels also cause

Answer 26

the cervical mucus becomes more water and more easily penetrated by sperm, leading to increased chance of fertilisation

Question 27

after ovulation what does the follicle turn into

Answer 27

corpus luteum

Question 28

what does the corpus luteum secrete

Answer 28

progesterone

Question 29

what does oestrogen and progesterone cause

Answer 29

further proliferation and vascularisation of the endometrium in preparation for receiving an embryo

Question 30

what happens towards the end of the luteal phase

Answer 30

progesterone concentration decreases

Question 31

give an example of negative feedback (females)

Answer 31

high oestrogen and progesterone levels inhibit LH and FSH secretion, when these levels drop, it causes the break down of the endometrium and FSH and LH are secreted again by the pituitary