Hypothalamic pituitary axis I and II

Question 1

What are the four classes of hormones?

Answer 1

Amino acid derivatives, Peptide and protein hormones, Steroid hormones and fatty acid compounds

Question 2

What are amino-acid derivative hormones?

Answer 2

any hormone derived from tyrosine (thyroid hormones and catelochomines)

Question 3

What are steroid derivative hormones?

Answer 3

Any hormone derived from cholesterol

Question 4

What are peptide hormones?

Answer 4

Chains of amino acids, all pituitary gland hormones

Question 5

What are fatty acid compound hormones?

Answer 5

Any hormone derived from arachidonic acid

Question 6

What is the hypothalamic pituitary portal system?

Answer 6

Two capillary beds in series,

Question 7

How does ADH get secreted?

Answer 7

The hypothalamus detects a decrease in blood volume and increase in osmolarity

Question 8

What happens to aquaporins when ADH concentrations are high?

Answer 8

More aquaporins are incorporated into the luminal membranes of the tubular cells so more water is absorbed from the collecting ducts

Question 9

What is the endocrine system?

Answer 9

A major regulatory system that coordinates life sustaining responses and functions

Question 10

What are some examples of ‘pure’ endocrine glands?

Answer 10

Pituitary, Pineal, Thyroid, Parathyroid and adrenal

Question 11

What are some organs that contain endocrine cells?

Answer 11

The pancreas, Thymus, Gonads and The hypothalamus

Question 12

What is a ‘pure’ endocrine gland?

Answer 12

A gland with no exocrine function that only secretes hormones

Question 13

What causes pituitary dwarfism?

Answer 13

Secretion of too little growth hormone in young animals

Question 14

What causes diabetes insipidus?

Answer 14

Secretion of too little ADH

Question 15

What causes Hypo/Hyper throidism?

Answer 15

Secretion of too much/ too little thyroid hormone

Question 16

What causes hypo-hyper calcaemia?

Answer 16

When the circulating calcium is too low/ too high

Question 17

What is hypo-/hyper parathyroidism?

Answer 17

Secretion of too much/ too little parathyroid hormone

Question 18

What part of the brain does the hypothalamus form part of the floor of?

Answer 18

The diencephalon

Question 19

What does the hypothalamus serve as a link for?

Answer 19

Serves as a link between the neuro and endocrine systems

Question 20

What is the pituitary gland also known as?

Answer 20

The hypophysis

Question 21

What links the pituitary gland to the hypothalamus?

Answer 21

The infundibulum

Question 22

What are the three parts of the pituitary?

Answer 22

Anterior lobe, Intermediate lobe and Posterior lobe

Question 23

Which lobe is an extension of the hypothalamus?

Answer 23

The posterior lobe/ neurohypophysis

Question 24

Where are the anterior and intermediate lobes derived from?

Answer 24

They are epithelial tissues and they are derived from the oral cavity

Question 25

What defining feature of the posterior lobe means that it is part of the CNS?

Answer 25

it is connected to the hypothalamus via axons

Question 26

What system connects the anterior/posterior lobes to the hypothalamus?

Answer 26

The hypothalamic pituitary portal system

Question 27

What two hormones are released by the posterior pituitary?

Answer 27

ADH and oxytocin

Question 28

How many amino acids make up both ADH and oxytocin?

Answer 28

9, 7 of which are conserved

Question 29

By what mechanism does ADH work?

Answer 29

via a negative feedback mechanism

Question 30

What is incorporated when ADH concentrations are high?

Answer 30

More aquaporins are added into the luminal membrane of the tubular cells

Question 31

What is Hypovolaemia and what detects it?

Answer 31

Hypovolaemia is detected by pressure sensors such as carotid and aortic baroreceptors and stretch receptors in the walls of the left atrium and the pulmonary vein Hypovolaemia

Question 32

What can cause diabetes insipidus?

Answer 32

Head trauma, infections and tumours of the hypothalamus

Question 33

What kind of mechanism releases oxytocin?

Answer 33

Positive feedback, useful for uterine contractions and contraction of myoepithelial cells in mammary alveoli

Question 34

What do releasing hormones do?

Answer 34

they increase secretion rate

Question 35

What do inhibitory neurones do?

Answer 35

they decrease secretion rate

Question 36

What are the 6 different anterior pituitary hormones?

Answer 36

ACTH, GH, FSH, LH, Prolactin, TSH

Question 37

What are the 5 different types of endocrine cells in the anterior pituitary?

Answer 37

Gonadotrophs, Somatotrophs, Corticotrophs, Thyrotrophs, and lactotrophs

Question 38

What is long-loop feedback?

Answer 38

Hormones released from the peripheral endocrine gland provides feedback to the pituitary or hypothalamus

Question 39

What is short loop feedback?

Answer 39

Hormone from the pituitary provides feedback to the hypothalamus

Question 40

What is ultra short feedback?

Answer 40

The hormone released by the endocrine organ directly provides feedback to the endocrine organ of origin

Question 41

What is the most abundant hormone produced by the anterior pituitary?

Answer 41

Growth hormone

Question 42

How many amino acids are in growth hormone?

Answer 42

191

Question 43

What are the two hypothalamic hypophysiotrophic hormones that regulate the release of GH?

Answer 43

GHRH, and GHIH

Question 44

What is prolactin?

Answer 44

A peptide hormone consisting of a single chain (198 amino acids)- it stimulates the production of milk and development of the mammary gland

Question 45

What two hormones regulate the secretion of Prolactin?

Answer 45

PRH and dopamine (PIH)

Question 46

Why can you do direct release of neuroendocrine cells into the first capillary bed?

Answer 46

Because there is no BBB

Question 47

What is the Blood Brain Barrier?

Answer 47

Network of blood vessels and tissues, made up of closely spaced cells that keep harmful substances form reaching the brain

Question 48

What is Diuresis?

Answer 48

Excessive production of urine

Question 49

What pressure sensors detect hypovolaemia?

Answer 49

pressure sensors e.g carotid and aortic baroreceptors and stretch receptors in the wall of the left atrium

Question 50

What is produced by the liver when growth hormone acts on it?

Answer 50

IGF-1 (insulin-like growth hormone)

Question 51

What is the effect of somatostatin on growth hormone?

Answer 51

it inhibits GH secretion