Hypothalamus, pituitary, pineal 26

Question 1

Hypothalamic nerve cells synthesise how many hormones?

Answer 1

At least nine.

Question 2

Pituitary endocrine nerve cells synthesise how many hormones?

Answer 2

At least seven.

Question 3

What do both hypothalamus and pituitary cells work together to regulate?

Answer 3

growth, development, metabolism, homeostasis.

Question 4

What do hypophyseal portal veins do?

Answer 4

They connect capillaries in hypothalamus to capillaries in anterior pituitary.

Question 5

Where is the pituitary gland found in the body?

Answer 5

Two lobes in the anterior and posterior in the head.

Question 6

Explain the steps to regulating release of anterior pituitary hormones.

Answer 6

1) Hypothalamic neurosecretory cells end near capillaries of hypothalamus.
2) Secrete releasing hormones or inhibiting hormones through hydrophyseal portal veins
3) Regulates release of anterior pituitary hormones.

Question 7

What is the anterior pituitary/ adenohypophysis known as?

Answer 7

Human growth hormone (hGH)

Question 8

What does the human growth hormone do?

Answer 8

Promotes synthesis of insulin-like growth factors (IGFs) = somatomedins, in liver, muscle, cartilage and bone.

Question 9

How is human growth hormone released?

Answer 9

Released in bursts, 2 hour intervals.

Question 10

What releases ‘growth hormone releasing hormone’ (GHRH) & ‘growth hormone inhibiting hormone’ (GHIH)?

Answer 10

Hypothalamus.

Question 11

How does hypoglycaemia do to GHRH & GHIH?

Answer 11

low blood sugar, produces more GHRH & less GHIH

Question 12

what does hyperglycaemia do to GHRH & GHIH?

Answer 12

high blood sugar, inhibits GHRH & producing more GHIH.

Question 13

What does the thyroid stimulating hormone do?

Answer 13

Stimulates the synthesis & secretion of thyroid hormones from the thyroid gland.

Question 14

What regulates the thyrotropin releasing hormone?

Answer 14

Circulating thyroid hormone levels.

Question 15

Describe follicle stimulating hormone females. (FSH)

Answer 15

FSH initiates follicle development in ovaries.

Question 16

Describe follicle stimulating hormone in males.

Answer 16

FSH stimulates sperm production in testes.

Question 17

Describe the role of Luteinising hormone in females.

Answer 17

LH with FSH stimulates ovulation, forms corpus luteum & secretes progesterone.

Question 18

Describe the role of luteinising hormone in males.

Answer 18

stimulates release of testosterone.

Question 19

With high levels of oestrogen or testosterone, what happens to the gonadotrophin releasing hormone? (GnRH)

Answer 19

It is suppressed.

Question 20

What does the anterior pituitary hormone ‘prolactin’ do?

Answer 20

initiates & maintains milk production by mammary glands.

Question 21

What hormone does not have an inhibiting hormone?

Answer 21

Thyroid.

Question 22

What stimulates prolactin releasing hormone?

Answer 22

High levels of oestrogen (during pregnancy).

Question 23

What does adrenocorticotrophic hormone (ACTH) do?

Answer 23

controls production & secretion of glucocorticoids (cortisol) from adrenal cortex.

Question 24

What hormone stimulates ACTH?

Answer 24

Corticotrophin releasing hormone from hypothalamus.

Question 25

What inhibits CRH & ACTH release?

Answer 25

Adrenal glucocorticoids - - called negative feedback

Question 26

what does melanocyte-stimulating hormone (MSH) do?

Answer 26

Appears in small circulating amounts, excess causes skin darkening.

Question 27

Where are posterior pituitary hormones synthesised?

Answer 27

In the hypothalamus.

Question 28

Where are posterior pituitary hormones stored prior to release?

Answer 28

They travel down nerve axons to terminals in posterior pituitary gland where they are stored.

Question 29

What hormones are from the posterior pituitary gland?

Answer 29

oxytocin & antidiuretic hormone (ADH).

Question 30

Describe the hormone oxytocin.

Answer 30

Allows milk ejecting, enhances smooth muscle uterine contraction during birth, might play a role in emotional connection.

Question 31

Describe antidiuretic hormone. (ADH) = vasopressin

Answer 31

Causes kidneys to retain more water, causes vasoconstriction which increases blood pressure. high blood osmotic pressure (high conc. of solutes detected in hypothalamus = increase in secretion.

Question 32

What is the Pineal gland?

Answer 32

a small gland attached to the roof of the third ventricle of brain.

Question 33

What does the pineal gland do?

Answer 33

Produces melatonin, sets the body's biological clock.