Physiology

Question 1

Does the endocrine system involve ducts?

Answer 1

Answer: No it is a ductless system involving glands that secrete directly into blood.

Question 2

How is specificity of signalling by endocrine glands achieved?

Answer 2

Answer: chemically distinct hormones, specific hormone receptors and distinct distribution of receptors.

Question 3

List the main endocrine glands of the body

Answer 3

Answer: (1) hypothalamus (2) pituitary (3) parathyroid (4) thyroid (5) adrenal glands (6) pancreas (7) placenta (8) ovaries and testes.

Question 4

What is meant by autocrine gland?

Answer 4

Answer: hormone release acts back on the structure that released it.

Question 5

What is meant by a paracrine gland?

Answer 5

Answer: hormone release acts on neighbouring structures.

Question 6

List the 3 main classes of hormones

Answer 6

Answer (1) glycoproteins and peptides (2) steroids (3) tyrosine derivatives.

Question 7

Give an example of glycoprotein/peptide hormones

Answer 7

Answer: (1) insulin (2) growth hormone (3) oxytocin and (4) prolactin.

Question 8

Give an example of a steroid hormone?

Answer 8

Cortisol and Testosterone

Question 9

Give an example of a tyrosine-derivative hormone?

Answer 9

Adrenaline, Thyroid Hormone and Melatonin

Question 10

A whole protein is always required to achieve hormonal effect. Is this statement true or false?

Answer 10

Answer: False as a protein can be cleaved into active hormonal units

Question 11

On a basic level how are amines, peptides and proteins released from their respective endocrine cell?

Answer 11

Synthesised then packaged into vesicles and released in response to a stimuli via exocytosis

Question 12

On a basic level, how are steroid hormones released from the endocrine cell?

Answer 12

Synthesised upon demand then stimuli increases cellular uptake and availability of cholesterol and rate of conversion into pregnenolone which is then used to build steroids to be released

Question 13

Steroid hormones travel freely in blood. True or false?

Answer 13

False as usually has a carrier protein in inactive form.

Question 14

Which carrier protein binds cortisol?

Answer 14

Cortisol binding protein

Question 15

Which carrier protein binds thyroxine (T4?)

Answer 15

Thryoxine-binding globulin

Question 16

Which hormone usually binds to sex steroid-binding protein?

Answer 16

Testosterone and Oestradiol

Question 17

What does topic mean with regards to hormone action?

Answer 17

Refers to a hormone that acts upon another endocrine gland to regulate secretion of hormone.

Question 18

What organs in the body have the greatest role in elimination of hormones?

Answer 18

Answer: Liver and Kidney

Question 19

Time taken to reach half life of amine hormones is achieved in?

Answer 19

Answer: Seconds

Question 20

Time taken to reach half life of protein hormones

Answer 20

Minutes

Question 21

Time taken to reach half life of steroid hormones is achieved in?

Answer 21

Hours

Question 22

List the 3 main distinct types of hormone receptors

Answer 22

GPCR
Receptor Kinases
Nuclear Receptors

Question 23

Which of the 3 main types of hormone receptor are cell surface receptors?

Answer 23

GPCR and Receptor Kinases

Question 24

Which of the 3 main types of hormone receptors are intracellular receptors?

Answer 24

Nuclear Kinases

Question 25

Describe Class 1 nuclear receptors

Answer 25

Activated by steroid hormones, usually in cytoplasm bound to HSPs

Question 26

Describe class 2 nuclear receptors

Answer 26

Activated by lipids and present in nucleus