Hormonal control of growth,

Question 1

when are insulin and insulin like growth factors important during in terms of group?

Answer 1

pre-natal and post-natal development

Question 2

what is growth hormones important for in terms of growth?

Answer 2

post natal development

Question 3

what is thyroid hormones important for in terms of growth

Answer 3

pre-natal brain development and post natal development

Question 4

what are sex hormones important for in terms of growth?

Answer 4

growth and development during puberty

Question 5

what is growth hormone secreted by?

Answer 5

somatotrophic cells in the anterior pituitary

Question 6

what effect does an increase in cAMP have on GH?

Answer 6

increased secretion

Question 7

when is the amplitude of secretory pulses of GH highest?

Answer 7

at night, particularly after onset of sleep

Question 8

where is new bone tissue added?

Answer 8

epiphyseal growth plate

Question 9

what happens when the epiphyseal growth plate closes?

Answer 9

no more bone growth can occur

Question 10

what are chondrocytes?

Answer 10

add new cartilage to the bone pushing it up until the plate closes

Question 11

what do osteoblasts do?

Answer 11

convert cartilage to bone

Question 12

what does IGF stimulate?

Answer 12

promoted cell division of chondrocytes to make the bone grow more

Question 13

where is growth hormone released?

Answer 13

anterior pituitary

Question 14

what is growth hormone secretion under the control of?

Answer 14

hypothalamic hormones

Question 15

how does thyroid hormone affect growth?

Answer 15

stimulates GH synthesis
potentiate the effect of GH and IGF on bone growth
Promotes differentiation of chondrocytes

Question 16

what sex hormones are highest in males?

Answer 16

testosterone and dihydrotestosterone

Question 17

what sex hormones are highest in females?

Answer 17

estrogen
progesterone

Question 18

what is sex hormones synthesis regulated by?

Answer 18

gonadotrophins

Question 19

what is the peptide kisspeptin important for

Answer 19

the onset of puberty
this triggers GnRH release from neurons in the hypothalamus

Question 20

what cells make testosterone?

Answer 20

leydig and sertoli

Question 21

what works on leydig cells?

Answer 21

luteinizing hormone

Question 22

what works on sertoli cells?

Answer 22

follicular stimulating hormone

Question 23

what receptor does estrodiol work on?

Answer 23

estrogen receptor

Question 24

what receptor does testosterone and DHT work on

Answer 24

they work on the same androgen receptor which has different effects

Question 25

what is the main target of testosterone?

Answer 25

muscle

Question 26

where is the main target of DHT ?

Answer 26

skin/prostate

Question 27

where is the main target of estrodiol?

Answer 27

bone

Question 28

what is the main effects of testosterone on growth?

Answer 28

stimulate secretion of GH stimulate protein synthesis in many tissues

Question 29

what regulates release of oestrogen and progesterone in women?

Answer 29

LH and FSH

Question 30

what is the growing follicle ?

Answer 30

stimulates release of oestrogen

Question 31

what is corpus luteum?

Answer 31

stimulates release of progesterone and some oestrogen

Question 32

what is the ovarian cycle?

Answer 32

describes changes occurring in the follicles of the ovary

Question 33

what is the uterine cycle?

Answer 33

describes changes that occur in the endometrial lining of the uterus

Question 34

what triggers ovulation

Answer 34

LH surge

Question 35

what happens if pregnancy doesn’t occur

Answer 35

the corpus luteum degrades leading to a fall in oestrogen and progesterone which causes FSH and LH to rise

Question 36

what does the hormone changes do the endometrium?

Answer 36

oestrogen and progesterone stimulate the thickening and development of the endometrium in preparation for possible pregnancy

Question 37

what is human chorionic gonadotrophin?

Answer 37

- a hormone that is released from the conceptus (develops from fertilised egg) - Prevents degeneration of the corpus luteum

Question 38

when do HCG levels rise until?

Answer 38

the placenta takes over and produces progesterone and oestrogen

Question 39

what does progesterone inhibit?

Answer 39

contraction to prevent premature delivery

Question 40

what is menopause caused by?

Answer 40

failure of the ovaries to respond to gonadotrophins

Question 41

what condition may occur in menopause and why?

Answer 41

osteoporosis because oestrogen is a bone protective hormone

Question 42

what is detected by pregnancy tests?

Answer 42

human chorionic gonadotrophic

Question 43

what does tests for fertility measure?

Answer 43

LH