L21- Hormonal Control Of Growth, Development And Reproduction

Question 1

Hormones involved in growth and their function

Answer 1

Insulin like growth factors- important during prenatal and post natal development
Growth hormone- important for post natal development
Thyroid hormone - important for prenatal brain development and post-natal development
Sex hormones- are important for growth and development

Question 2

Growth hormone is a ____ hormone secreted by ________in the ________

Answer 2

Peptide hormone secreted by somatotropic cells in anterior pituitary

Question 3

What does GH do

Answer 3

Main stimulus for somatic growth
Promotes synthesis and secretion of IGF1

Question 4

What are most effects of GH on growth mediated by

Answer 4

IGF1

Question 5

How does secretion of growth hormone occur

Answer 5

In discrete but irregular pulses, between pulses GH levels can be undetectable

Question 6

Secretion of GH is maximal when?

Answer 6

At night
In children
During puberty

Question 7

New bone tissue is added to what region

Answer 7

Epiphyseal growth plate

Question 8

what hormones stimulate bone growth

Answer 8

GH and IGF1

Question 9

GH stimulates differentiation of

Answer 9

Precursor cells in epiphyses plate into chondrocytes

Question 10

IGF1 acts in a ______manner to stimulate_______

Answer 10

Paracrine manner to stimulate chondrocyte cell division

Question 11

Other important effects of growth hormone / IGF1

Answer 11

Stimulates protein stnthesis in muscle/orher cell types (GH)
Increases levels of circulating energy sources (GH)
IGF1 powerful mitogen, promoting cell growth and division

Question 12

Thyroid hormone roles

Answer 12

Stimulate GH synthesis
Potentates effects of GH and IGF1
Promotes differentiation of chondrocytes

Question 13

Sex hormone synthesis is regulated by

Answer 13

Gonadotrophins (FSH/LH)

Question 14

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Question 15

Proximal event of onset of puberty

Answer 15

Increase in pulsation GnRH secretion

Question 16

Important of kisspeptin

Answer 16

Triggers GnRH release from GnRH hormones in hypothalamus

Question 17

What can testosterone be converted to

Answer 17

DHT and estradiole

Question 18

Sex hormones are mainly secreted by

Answer 18

Adrenal cortex

Question 19

What regulates release of oestrogen and progesterone

Answer 19

LH and FSH

Question 20

Ovarian cycle

Answer 20

Changes in follicles of ovary

Question 21

Uterine cycle

Answer 21

Changes in endometrial lining of uterus

Question 22

What regulates uterine cycle

Answer 22

Oestrogen/progesterone released by ovaries

Question 23

Hormone level fluctuation (oestrogen)

Answer 23

FSH LH stimulate oestrogen release. One follicle becomes dominant and secretes high oestrogen levels.
This surge exerts positive feedback so there’s a surge of LH and FSH
LH surge triggers ovulation

Question 24

Hormone fluctuation (combined)

Answer 24

Corpus pursue forms secreting High oestrogen and progesterone
Negative feedback leads to low FSH LH
If pregnancy doesn’t occur corpus luteum degrades so fall in oestrogen progesterone FSH LH

Question 25

£94’

Question 26

What stimulates thickening of rndomrtrium

Answer 26

Oestrogen and progesterone

Question 27

What prevents degeneration of corpus luteum in pregnancy

Answer 27

HCG

Question 28

Cause of menopaus

Answer 28

Failure of ovaries to respond to gondatropins
Low oestrogen