Endocrine System

Question 1

What is homeostasis?

Answer 1

A state of overall internal chemical and physical stability that is required for the survival of cells and the body

Question 2

What do homeostatic mechanisms do?

Answer 2

Maintain a constant internal environment despite a variable external environment

Question 3

What does deviation from homeostasis indicate?

Answer 3

Disease

Question 4

What is a set point?

Answer 4

The physiological value around which the normal range fluctuates

Question 5

What is a negative feedback loop?

Answer 5

A feedback loop where the the effect opposes the original stimulus

Question 6

What are the elements of a feedback loop?

Answer 6

Stimulus, receptor, integrator, effector, response

Question 7

What is positive feedback?

Answer 7

Where the response increases the original stimulus

Question 8

What are the two types of hormones?

Answer 8

Lipid hormones

Non lipid hormones, peptides

Question 9

Pathway of steroids hormones

Answer 9

• lipid soluble - diffuse directly through the cell membrane
• enter the cytoplasm
• enter the nucleus
• form a hormone receptor complex (transcription factor)
• binds to promoter regions of genes
• stimulates or inhibits the transcription of those genes

Question 10

Pathway of peptide hormones

Answer 10

• binds to a receptor on the cell membrane

- activates a Secondary messenger

Question 11

Paracrine

Answer 11

Hormone stimulates a nearby cell, travels through extra cellular material

Question 12

Autocrine

Answer 12

The hormone secretion acts on the cell itself or cell type

Question 13

Which hormones does the anterior pituitary secrete?

Answer 13

ACTH, TSG, FSH, LH, GH, prolactin

Question 14

Which hormones does the posterior pituitary produce?

Answer 14

ADH, oxytocin

Question 15

What does the adrenal cortex secrete?

Answer 15

Cortisol, aldosterone, sex hormones

Question 16

What does the adrenal medulla secrete?

Answer 16

Adrenaline and noradrenaline

Question 17

What do the ovaries and testes secrete?

Answer 17

Sex hormones

Question 18

What does the pineal gland secrete?

Answer 18

Melatonin

Question 19

What does the thyroid secrete?

Answer 19

Thyroid hormone

Calcitonin

Question 20

What does thyroid hormone do?

Answer 20

Regulates metabolism

Question 21

What does calcitonin do?

Answer 21

Lowers blood Ca2+

Question 22

What do the parathyroid glands secrete?

Answer 22

Parathyroid hormone

Question 23

What does parathyroid hormone do?

Answer 23

Regulates blood calcium levels

Question 24

What are normal blood glucose levels?

Answer 24

Fasting: 4.0 - 5.4mmol/L

After a meal: <7.8mmol/L

Question 25

What is the exocrine function of the pancreas?

Answer 25

Secretion of digestive enzymes

Question 26

Hypothalamus-pituitary-thyroid axis

Answer 26

- hypothalamus releases thyrotropin releasing hormone - anterior pituitary releases thyroid stimulating hormone - thyroid releases thyroid hormone - thyroid hormones have negative feedback on the hypothalamus and anterior pituitary

Question 27

What is hypothyroidism?

Answer 27

Low levels of thyroid stimulating hormone

Question 28

What is hyperthyroidism?

Answer 28

High levels of thyroid hormone

Question 29

What are symptoms of hypothyroidism?

Answer 29

Fatigue Weight gain Intolerance to cold temperatures Dry skin

Question 30

What are the symptoms of hyperthyroidism?

Answer 30

``` High heart rate High blood pressure Heavy sweating Heat intolerance Weight loss ```

Question 31

What is pituitary dwarfism?

Answer 31

Underproduction of GH or insensitivity of receptors to GH during childhood

Question 32

What happens to effective circulating blood volume and blood pressure when someone is bleeding internally?

Answer 32

They both drop

Question 33

What causes and increase in blood pressure in the bleeding internally case?

Answer 33

Sympathetic nervous system - adrenaline

Question 34

Effect of adrenaline on sweat glands and blood vessels of the skin

Answer 34

- blood vessels constrict | - sweat glands stimulated to secrete

Question 35

What is hypovolemic shock?

Answer 35

An emergency condition in which severe fluid or blood loss makes the heart unable to pump enough blood to the body

Question 36

What are some symptoms of hypovolemic shock?

Answer 36

- rapid heartbeat - low blood pressure - nauseous - thirsty - rapid shallow breathing - weakness

Question 37

Internal bleeding case: what type of cellular respiration will the casualties non essential organs be using?

Answer 37

Anaerobic - results in a build up in lactic acid which decreases neural function

Question 38

Internal bleeding case: why is the casualty nauseous?

Answer 38

Lack of blood flow to the gut

Question 39

What happens to cells if there is insufficient insulin in a diabetic?

Answer 39

Cells are starved of energy since they cannot use the glucose in the blood

Question 40

What is a byproduct of the breakdown of fat?

Answer 40

Ketones - volatile, blown off at the lungs

Question 41

What happens when ketones build up in the blood?

Answer 41

Ketoacidosis