The Endocrine System

Question 1

Endocrine signaling

Answer 1

Secretion of hormones directly into the bloodstream.

Question 2

Hormones

Answer 2

Signaling molecules that travel to distant target tissues, where they bind to receptors and induce a change in gene expression or cell function

Question 3

Hormone Classification

Answer 3

• Peptides

-Steroids

• Amino Acid Derivatives

Question 4

Peptide Hormones

Answer 4

• Hormones made of amino acids
• Water soluble (Hydrophilic) and can’t pass the lipid bilayer of cells
• They bind to receptors on the cell surface (Extracellular receptors).
• Use second messengers ( CAMP, IP3, Ca+2)
• Act quickly but short time frame
• Travel freely in blood ( No carrier proteins needed)

Question 5

Example of peptide hormones

Answer 5

• Insulin
• Glucagon
• ADH (Vasopressin)
• Oxytocin
  -TSH
• FSH
• PTH
• Calcitonin
• GH (Growth Hormone)
• ACTH
  -LH
• Inside Glands, All Old Teachers Finally Passed Clinical Guidelines Alongside Lectures

Question 6

Steroid Hormones

Answer 6

• Derived from cholesterol
• Lipid-Soluble (Hydrophobic)
• Minimally polar and can pass through the plasma membrane
• Bind intracellular receptors
• Cannot dissolve in blood so they need carrier proteins (Albumin and Globulins)
• Slow but long lasting effects

Question 7

Example of Steroid Hormones

Answer 7

• Cortisol
• Aldosterone
• Estrogen
• Progesterone
• Testosterone
• CAMPT

Question 8

Amino Acid-Derivative Hormones

Answer 8

• Comes from a single amino acid, typically from tyrosine or tryptophan

Question 9

Examples of Amino acid - Derived Hormones

Answer 9

• Epinephrine
• Norepinephrine
• T3
• T4

Question 10

Hormones can be classified by

Answer 10

Target tissues

• Direct or Tropic Hormones

Question 11

Direct Hormones

Answer 11

Have major effects on non-endocrine tissues

Question 12

Tropic Hormones

Answer 12

Have major effects on other endocrine tissues

Question 13

Hypothalamus

Answer 13

• Bridge between the nervous and endocrine systems
• Release of hormones from the hypothalamus is mediated through projection from other parts of the brain, Chemo and baroreceptors in blood vessels, and negative feedback from other hormones

Question 14

Negative feedback

Answer 14

The final hormone of a pathway inhibits hormones earlier in the pathway, maintaining homeostasis

Question 15

What Hormones come from the hypothalamus?

Answer 15

• GnRH
• GHRH
• TRH
• CRF
• PIF (Dopamine)

Question 16

GnRH

Answer 16

Promotes the release of FSH and LH

Question 17

GHRH (Growth Hormone releasing hormone)

Answer 17

Promotes the release of growth hormone

Question 18

TRH (Thyroid Releasing Hormone)

Answer 18

Promotes the release of thyroid-stimulating hormone

Question 19

CRF (Corticotropin releasing factor)

Answer 19

Promotes the release of adrenocorticotropic hormone (ACTH)

Question 20

PIF / Dopamine (Prolactin inhibiting factor)

Answer 20

Inhibits the release of prolactin

Question 21

Hormones from Anterior pituitary

Answer 21

• FSH
• LH
• ACTH
• TSH
• Prolactin
• Endorphins
• GH (Growth Hormone)

Question 22

FSH

Answer 22

Promotes the development of ovarian follicles in females and spermatogenesis in males

Question 23

LH

Answer 23

Promotes ovulation and testosterone production in males

Question 24

Adrenocorticotropic Hormone (ACTH)

Answer 24

Promotes the synthesis and release of glucocorticoids from the adrenal cortex

Question 25

TSH

Answer 25

Promotes the synthesis and release of triiodothyronine and thyroxine from the thyroid

Question 26

Prolactin

Answer 26

Promotes milk production

Question 27

Endorphins

Answer 27

Decrease perception of pain and can produce euphoria

Question 28

GH

Answer 28

Promotes the growth of bone and muscle and shunts glucose to these tissues. It raises blood glucose concentrations

Question 29

What hormones come from the Posterior pituitary?

Answer 29

- ADH - Oxytocin

Question 30

Antidiuretic Hormone (ADH)

Answer 30

Secreted in response to low blood volume or increased blood volume or increased blood osmolarity and increases reabsorption of water in the collecting duct of the nephron, increasing blood volume and decreasing blood osmolarity

Question 31

Oxytocin

Answer 31

- Secreted during childbirth promotes uterine contraction and milk ejection -Positive feedback

Question 32

What hormones come from the thyroid ?

Answer 32

- T3 -T4 - Calcitonin

Question 33

T3 (Triiodothyronine) and T4 (Thyroxine)

Answer 33

- Produced by follicular cells and contain iodine - Increase metabolic rate and alter the use of glucose and fatty acids

Question 34

Calcitonin

Answer 34

- Produced by parafollicular cells - Decreases plasma calcium concentration by promoting calcium excretion in the kidneys

Question 35

What Hormone is released from the parathyroid gland?

Answer 35

PTH

Question 36

Parathyroid Hormone

Answer 36

- Increases blood calcium concentration - Decreases the excretion of calcium by the kidneys and increases bone resorption directly to increase blood calcium concentration - Activates vitamin D, which is needed for calcium to be absorbed in the gut

Question 37

Adrenal cortex

Answer 37

Has three classes of steroid hormones - Glucocorticoids (Cortisol and Cortisone) - Mineralocorticoids (Aldosterone) - Cortical sex hormones (Androgens and estrogens)

Question 38

Cortisol and Cortisone

Answer 38

- Released by the stimulation of ACTH - Increase blood glucose concentration, reduce protein synthesis, inhibit the immune system

Question 39

Aldosterone

Answer 39

- Regulated by renin-angiotensin-aldosterone - Promotes Salt reabsorption and increases potassium and hydrogen ion excretion

Question 40

Androgens

Answer 40

male sex hormones

Question 41

Estrogens

Answer 41

Both in males and females

Question 42

Adrenal medulla

Answer 42

Derived from the nervous system and secretes catecholamines into the bloodstream

Question 43

What hormones are released from the adrenal medulla ?

Answer 43

Epinephrine and norepinephrine

Question 44

Epinephrine and norepinephrine

Answer 44

involved in the fight or flight (Sympathetic response) - Promote glycogenolysis, increase basal metabolic rate, increase heart rate, dilate the bronchi, and alter blood flow

Question 45

What hormones come from the pancreas ?

Answer 45

- Glucagon - Insulin - Somatostatin

Question 46

Glucagon

Answer 46

- Produced by alpha cells - Raises blood glucose levels by stimulating protein and fat degradation

Question 47

Insulin

Answer 47

- Produced by Beta cells - Lowers blood glucose levels by stimulating glucose uptake by cells and promoting anabolic processes like glycogen, fat, and protein synthesis

Question 48

Somatostatin

Answer 48

- Inhibits insulin and glucagon secretion

Question 49

What hormones come from the gonads ?

Answer 49

- Testosterone - estrogen - Progesterone

Question 50

Testosterone

Answer 50

Come from the testes

Question 51

Estrogen and progesterone

Answer 51

Come from the ovaries

Question 52

What hormone can be released from Pineal Gland ?

Answer 52

Melatonin

Question 53

Melatonin

Answer 53

Helps regulate circadian rhythms

Question 54

Cells in the stomach and intestine produce what hormones ?

Answer 54

Secretin, gastrin, and cholecytokinin

Question 55

What do kidneys secrete?

Answer 55

Erythropoietin

Question 56

Erythropoietin

Answer 56

Stimulates bone marrow to produce erythrocytes (red blood cells) in response to low oxygen levels in the blood

Question 57

Atrial natriuretic peptide (ANP)

Answer 57

- Secreted from the atria of the heart - Promotes excretion of salt and water in the kidneys in response to stretching of the atria (high blood volume)

Question 58

Thymosin

Answer 58

- Secreted from the thymus - Important for proper T-cell development and differentiation