5 Endocrine System

Question 1

Define a hormone

Answer 1

A chemical substance produced by a gland, carried by blood, which alters the activity of one or more target organs and is destroyed by the liver

Question 2

Describe lipid soluble hormones

Answer 2

It binds to nuclear receptors and travels along the blood stream bound to binding proteins

Question 3

Describe water soluble hormones

Answer 3

It binds to cell surface receptors and can dissolve in the plasma of the blood. Many circulate as free hormones and are delivered to target without binding to a protein

Question 4

By binding to receptors, what can hormones do?

Answer 4

1) alter plasma membrane permeability/ opening closing channels
2) stimulate synthesis of enzymes and other proteins within cell
3) activates/deactivates enzymes
4) induced secretory activity
5) stimulates nuclear/ cell division

Question 5

What glands are exclusively endocrine?

Answer 5

Pituitary
Thyroid
Parathyroid
Adrenal
Pineal

Question 6

Exocrine glands vs endocrine glands?

Answer 6

Secrete their products into ducts that carry the secretion to target area VS secrete their products (hormones) into interstitial fluid (bloodstream): ‘ductless’

Question 7

What are the three causes of hormone secretion

Answer 7

Hormonal stimuli
Humoral stimuli
Neural stimuli

Question 8

Describe hormonal stimuli

Answer 8

1) hypothalamus secretes hormone
2) hormone produced by cells in hyp travel to anterior pituitary gland
3) hormone regulates secretion of anterior pituitary hormones
4) anterior pituitary hormones travel to target cells

Question 9

Describe humoral stimuli

Answer 9

No idea bro, something like insulin and glucagon

Question 10

Insulin VS glucagon

Answer 10

Insulin lowers blood glucose levels, lowers blood fatty acids, and lowers blood amino acid level

Glucagon increases blood glucose levels, increase blood fatty acids

Question 11

Pathway of insulin regulation

Answer 11

Stimulus: change in blood glucose levels (increased)
beta cells of pancreas stimulated to secrete insulin to body cells which lead to the decrease in blood glucose levels and it returns to normal

Question 12

Pathway of glucagon regulation

Answer 12

Stimulus: decrease in blood glucose levels
Alpha cells of pancreas stimulated to secrete glucagon which go to liver cells and increase in blood glucose levels back to normal.

Question 13

What is pancreatic acini

Answer 13

Acinar cells which produce digestive enzymes secretes through a duct. (Exocrine)

Question 14

What is pancreatic islets (islets of langerhans)

Answer 14

Alpha cells and beta cells products directly secreted into bloodstream (endocrine)

Question 15

What is the neural stimuli pathway

Answer 15

1) hypothalamus secretes hormones
2) hormones transported to posterior pituitary gland and stored
3) when nerve impulses are fired, hormones are released into blood

Question 16

Describe adrenaline pathway

Answer 16

Stimulus: stress

The hypothalamus reacts to stimulus by sending nerve impulses travel along neurons to the spinal chord. Nerve impulses travel along another neuron to the adrenal medulla to release adrenaline.

Responses: increase in heart rate, increase in blood pressure, glycogen -> glucose

Question 17

Insulin regulation and action regarding lowering blood glucose levels

Answer 17

1) stimulates glycogenesis (glycogen from glucose)
2) inhibits glycogenolysis (glycogen to glucose)
3) inhibits glyconeogenesis (amino acids to glucose)
4) increase glucose transporters

Question 18

Glucagon regulation and action regarding increasing blood glucose levels

Answer 18

1) decreases glycogenesis (glycogen from glucose)
2) stimulates glycogenolysis (glycogen to glucose)
3) stimulates glyconeogenesis (amino acids to glucose)

Question 19

Insulin regulation and action regarding lowering blood fatty acid levels

Answer 19

Inhibits lipolysis

Question 20

Glucagon regulation and action regarding increase blood fatty acid levels

Answer 20

Stimulates lipolysis

Question 21

Name the four endocrine disorders

Answer 21

Hypersecretion
Hyposecretion
Hyperresponsiveness
Hyporesponsiveness