L-26

Question 1

What is the hypothalamus?

Answer 1

In many hormonal systems the hypothalamus is the control centre, comparing the current state to the set point and setting the appropriate response in motion. It is connected to the pituitary gland which releases hormones

Question 2

What is the pituitary gland?

Answer 2

Endocrine gland located at the base of the brain and attached inferiorly to the hypothalamus which controls the secretion of its hormones.

Question 3

How is the posterior lobe connected to the hypothalamus?

Answer 3

Through neurons with cell bodies in the hypothalamus and axon terminals in the PP.

Question 4

How does the hypothalamus cause hormone release in the posterior pituitary?

Answer 4

AP’s travel down axons and release stored hormones in axon terminals into the bloodstream.

Question 5

What hormones are released from the posterior pituitary?

Answer 5

• ADH ( anti-diuretic hormone)

- oxytocin

Question 6

What does ADH do?

Answer 6

Abs on kidney to promote water retention and is important for blood pressure and volume

Question 7

What does oxytocin do?

Answer 7

Key hormone in childbirth and breast feeding

Question 8

How is the anterior lobe connected to the hypothalamus?

Answer 8

Through a network of capillaries called portal vessels

Question 9

How does the hypothalamus signal release of Anterior pituitary hormones?

Answer 9

• hypothalamus secretes releasing hormones in similar way to PP hormones except the axon is short and axon terminals are within an area called to median eminence
• releasing hormones travel through bloodstream to anterior pituitary where they bind to cell surface receptors
• this stimulates a second messenger response that stimulates the release of hormone from the anterior pituitary

Question 10

What are the direct effects of growth hormone

Answer 10

Muscle- stimulates protein synthesis (long term) and inhibits cellular uptake of glucose (short term)
Liver- Stimulates glucose synthesis (short term)
Fat- increases triglyceride breakdown in adipose tissue (short term)

Question 11

What’s are the indirect effects of growth hormone?

Answer 11

Promotes growth of bone muscle and other tissues by causing the release of Somatomedin C from liver which promotes cell division

Question 12

When is growth hormone concentration highest?

Answer 12

During sleep

Question 13

What age is Growth hormone highest?

Answer 13

During puberty