Endocrine

Question 1

What does the endocrine system do

Answer 1

Release hormones into the bloodstream

Question 1

Functions of the endocrine system- Regulates fluids and electrolytes

Answer 1

3 hormones that regulate fluid and electrolyte blanace:
* ADH
* Aldosterone produced from cortex
* Atrial natriuretic peptode (ANP) produced by the heart.

Question 2

Functions of the ES- Coordinates the response to stress

Answer 2

When stressed hypothalamus signals the pituitary gland to produce hormones which signals the production of adrenal gland to increase produce cortisol

Question 3

Functions of ES- Regulates growth and metabolism

Answer 3

Thyroid galnds secretes thyroxin and triidothyronine. These stimulate growth, reproduction, development and metabolism.

Question 4

Functions of ES- Regulates reproduction

Answer 4

Endocrine glands in the reproductive system produce sex hormones such as testesterone and oestrogen.

Question 5

Difference between Endocrine glands and exocrine glands

Answer 5

Endocrine:
* Secrete hormones into the bloodstream
* No ducts
* Communication

Exocrine glands
* Secrete hormones into cavity or to skin
* Has ducts
* Digestion/lubrication/ protection

Question 6

Examples of Exocrine glands

Answer 6

Prostate gland
Mucous glands
Salivary glands

Question 7

Example of exocrine and endocrine glands in action in liver and pancreas

Answer 7

Exocrine:
Secretion of bile and pancreatic juices into the GI tract

Endocrine:
Secretion of insulin and glucagon into the blood stream.

Question 8

Homeostatic control centres of the endocrine system

Answer 8

Hypoythalamus- gland in brain which controls hormone system. It releases hormones to pituitary gland which secretes them to organs

Pituitary gland
Master gland. Tells other glands to release hormones

Individual endocrine galnds

Question 9

Parts of the pituitary glands

Answer 9

Anterior lobe of the pituitary produces 7 peptide hormones

Posterior lobe of the pituitary produces ADH and Oxytocin

Question 10

Hormones of the Anterior pituitary glands

Answer 10

Stimulate other endocrine glands to produce:
ACTH (adrenocorticotrophic hormone) –> Adrenal gland
TSH (thyroid stimulating hormone) –> Thyroid gland
FSH/LH follicle stimulating hormone/luteinising hormone → gonads

Or specific target tissues
PL prolactin → breast
* MSH melanocyte stimulating hormone → skin pigment
* GH growth hormone → muscle/bone

Question 11

Hormones of the posterior piyuiatary gland are..

Answer 11

Made in hypothalamus
Carried to the posterior pituitary
Released into the blood stream

e.g.
Oxytocin → uterus contraction
→ lactation

• ADH antidiuretic hormone → kidney (collecting ducts)

Question 12

What determines the size of the response

Answer 12

Number of receptors
Concentration of the hormone

Question 13

How are hormones regulated

Answer 13

Production:
Response to environmental challenge
Part of hormone cascade (negative/positive feedback)
Circadian rhythm

Loss:
Urine
Bile
Uptake by target tissue
Liver breakdown

Question 14

Hormone regulation- permissive

Answer 14

Where a hormone requires the previous effect of another hormone

e.g.
* Oestrogen = then progesterone on the uterus

Question 14

Hormone regulation- Antagonistic

Answer 14

Where two or more hormones oppose the effects of each other- antagonistic effect

e.g.
Blood glucose
* insulin causes blood glucose level to decrease
* glucagon causes blood glucose level to increase

Question 15

Hormone regulation- Synergistic

Answer 15

Two or more hormones complement each other simultaneously:

• Example:
• Milk production requires…
• oestrogen
• progesterone
• prolactin
• oxytocin
  …at the same time

Question 16

Hormones required for reproduction

Answer 16

FSH/LH from pituitary
* oestrogen
* Progesterone
* testosterone
* prolactin - milk duct development
* oxytocin - birth and lactation

Question 17

Pancreatic function

Answer 17

Contains islets of langerhans which secrete insulin and glucagon

They have 3 types of cells:
1) Alpha cells- secrete glucagon
2) Beta cells- secrete insulin
3) Delta cells- secretes digestive enzymes

Question 18

How insulin works

Answer 18

Stimulates the uptake of glucose to cells.
Conversion of gluocse into glycogen
stimulates entry of amino acis into cells and the synthesis of proteins
Decreases glycogenolysis and gluconeogenesis
Insulin binds to insulin receptors on cell membranes which allows for the GLUT4 channels to open so glucose can enter cells

Question 19

How Glucagon works

Answer 19

Glucagon is a hormone whose principle role is to increase blood glucose
levels when it falls below normal
* High glucose levels cause glucagon release to be inhibited
* Low glucose levels promote glucagon release, particularly in the liver

1.Glycogenolysis -the breakdown of glycogen to glucose
2.Gluconeogenesis -the formation of glucose from glycerol and proteins
rather than carbohydrates

Question 20

Stress response

Answer 20

initated by CNS and endocrine system
Corticotropin-releasing hormone (CRH) is released from
1. hypothalamus
2. sympathetic NS
3. pituitary gland
4. adrenal gland

The activation of these systems redirects adaptive energy to the CNS and stressed body sites

Question 20

Types of diabetes

Answer 20

Type 1- no insulin

Type 2 - Insulin resistance

Question 21

Central stress response

Answer 21

sympathetic NS is aroused during the stress response and causes medulla of the adrenal glands to release catecholamines into the blood stream

CRH stimulates pituitary gland to release variety of hormones including :

1) ADH and oxytocin
2) prolactin, endorphins, growth hormones and ACTH

ACTH stimulates the cortex of adrenal galnd to release cortisol

Question 22

Cortisol role

Answer 22

prodcued in the adrenal cortex within the adrenal gland
released in response to stress and low Blood sugar

It functions:
1. increase blood sugar through gluconeogenesis
2. Suppress the immune system
3. Aids in the metabolism of fat, protein and carbohydrates
4. Decreases bone formation
5. Increased blood pressure

Question 23

stages of sleep

Answer 23

Stage 1 light sleep, easy to wake, hallucination (hearing doorbell, seeing flash, falling sensation, images of the day)
Stage 2 harder to waken, K-complex, long term memories
Stage 3 and 4 very difficult to waken, sleep walking/talking
REM paradoxical sleep, eye movement, faster pulse, faster
breathing and brain active but skeletal muscle paralysis, dreaming

Question 24

Serotonin and Melatonin

Answer 24

The sleep wake cycle (body clock) is located in the suprachiasmatic
nucleus. It is sensitive to light.
* The pineal gland secretes serotonin during the day and
melatonin during the night.

Question 25

Sleep

Answer 25

Two major regulatory principles are involved:
* Homeostasis
* Circadian organization

Cortisol secretion has a circadian rhythm:
* Very low during the night (low stress)
* Raised during the day (stress)

Question 26

Consequences of sleep deprivation

Answer 26

Mental health:
Stress
Anxiety
Depression

CVD:
Angina pectoris
Hypertension

Reproductive effects
Spontaneous abortion
Low birth weight
Prematurity

Circadian rhythm disruption
Menstrual cycle
Respiratory rate
Body temp