Endocrine Mechanisms

Question 1

Main functional difference between endocrine and exocrine glands?

Answer 1

Exocrine glands only work locally and cannot affect organs in a distance

Question 2

Releases a product via exocytosis

Answer 2

Merocrine (Eccrine)

Ex. Sweat glands

Question 3

Releases products by membrane budding

Answer 3

Apocrine

Ex. Mammary glands

Question 4

Releases products via membrane rupture and cell lysis

Answer 4

Holocrine glands

Ex. Sebaceous glands

Question 5

T or F. Pancreas gland is both an exocrine and endocrine gland.

Answer 5

True. It releases digestive enzymes to GI tract through pancreatic duct and releases key hormones (insulin and glucagon)

Question 6

T or F. Some molecules can act as both neurotransmitters and hormones

Answer 6

True. Ex. Norepinephrine, oxytocin, and antidiuretic hormone (ADH)

Question 7

These hormones are one or multiple chains of amino acids (can be few amino acids to a lot)

Answer 7

Peptide hormones

Question 8

These hormones are derived from the lipid cholesterol

Answer 8

Steroid hormones

Question 9

T or F. The steroid hormones like lipid cholesterol contain its characteristic 5 ring structure

Answer 9

False. 4 ring structure!

Question 10

Steroid hormones are (hydrophobic/ hydrophilic) vs peptide hormone are (hydrophobic/ hydrophilic)

Answer 10

Steroid: hydrophobic
Peptide: Hydrophilic

Question 11

T or F. Peptide hormones can travel around the polar aqueous bloodstream without the need for blood transport proteins. However they cannot diffuses through cell membrane and therefore, binds to cell membrane receptors causing a cascade inside the cell through second messengers.

Answer 11

True

Question 12

Common secondary messengers

Answer 12

cAMP, IP3, and Ca2+

Question 13

T or F. Peptide hormones are associated with slow and long term changes

Answer 13

False. Rapid and short-term changes because they are hydrophilic

Question 14

T or F. Because of steroid hormone’s hydrophobicity, it requires a carrier protein to travel along the bloodstream

Answer 14

True

Question 15

Example of carrier proteins that shield steroid hormones to the environment

Answer 15

Sex hormone binding globulin and Albumin (binds a variety of nonpolar compounds)

Question 16

Steroid hormones influences the transcription which makes its effect (faster/ slower) and has (shorter/ longer) effects

Answer 16

Slower ; longer

Question 17

Steroid hormones production

Answer 17

The molecules are synthesized from cholesterol in the smooth ER and diffuse directly through the cell membrane into the vascular system

Question 18

Peptide hormones production

Answer 18

1. Transcription of relevant mRNA from associated DNA
2. Translation of mRNA into a polypeptide in ribosome
3. This polypeptide is called preprohormone-early precursor to mature peptide hormone
4. Preprohormone enter a secretory pathway for secretion from its cell of origin
5. during translation, the preprohormone is threaded into the rough ER where it become prohormone- immediate precursors of active peptide hormones
6. Travel to Golgi apparatus where they are cleaved by peptidases and sometimes modified by glycoslyation
7. Then they become fully functional peptide hormones
8. Leave golgi in vesicles and leave to circulation through exocytosis

Question 19

Hormones that are small molecules that are derived from a single amino acid

Answer 19

Amino acid derivatives

Question 20

T3 and T4 are derived from tyrosine and acts more like (peptide/ steroid) hormone

Answer 20

Steroid

Question 21

Epinephrine and norepinephrine acts more like (peptide/ steroid) hormone

Answer 21

Peptide (water-soluble)

Question 22

Epinephrine and norepinephrine are?

Answer 22

Catecholamines

Question 23

Melatonin is a derivative of which amino acid solubility property

Answer 23

Tryptophan ; amphipathic

Question 24

The nervous system is responsible for sensing changes in environmental conditions and then telling the endocrine system how to respond . The endocrine system is responsible for enacting these changes in the body

Answer 24

Neuroendocrine integration

Question 25

Stress hormone response

Answer 25

1. Hypothalamus secretes Cortictropin-releasing hormone (CRH) which binds to anterior pituitary gland 2. Anterior pituitary gland release adrenocorticotropic hormone (ACTH) tow act on adrenal cortex 3. Adrenal cortex secretes cortisol into circulation

Question 26

Steroid hormone released during periods of long-term stress. This increases metabolism of fats, proteins, and sugars

Answer 26

Cortisol

Question 27

Which part of the pituitary gland is hormonal and which is neuronal?

Answer 27

Anterior: hormonal Posterior: neuronal

Question 28

How is the hypothalamus and anterior pituitary gland connected

Answer 28

Hypophyseal portal system- endothelial cells are extremely permeable

Question 29

These secrete peptide hormones and receive hypothalamic input

Answer 29

Both anterior and posterior pituitary gland

Question 30

Posterior pituitary is a bunch of neuronal cell bodies or axons?

Answer 30

Axons with their cell bodies in the hypothalamus

Question 31

T or F. All the hormones released by posterior pituitary are synthesized in the hypothalamus

Answer 31

True

Question 32

2 hormones released by posterior pituitary

Answer 32

Oxytocin and antidiuretic hormone (ADH) or vasopressin

Question 33

This hormone blocks diuresis (urine formation) when de hydrated

Answer 33

ADH

Question 34

2 hormones released by anterior pituitary without go signal from hypothalamus

Answer 34

Prolactin and endorphins

Question 35

Low blood pressure and increase blood osmolality will cause (release/ no release) of ADH

Answer 35

Release

Question 36

T3 and T4 increase what rate?

Answer 36

Metabolic

Question 37

Hypothyroidism means (lower/ higher metabolic rate?

Answer 37

Lower- cause fatigue and weight gain

Question 38

Hyperthyroidism mean (lower/ higher) metabolic rate?

Answer 38

Higher- cause weight loss and higher heart rate

Question 39

Thyroid releases a hormone that reduces calcium concentration in the bloodstream, promoting calcium storage in bone and increase urinary excretion of calcium

Answer 39

Calcitonin

Question 40

Which hormone opposes the effect of calcitonin by increasing circulating calcium levels by promoting calcium absorption in the intestine and reduce calcium storage and calcium urine excretion

Answer 40

Parathyroid hormone

Question 41

Adrenal cortex release what hormones?

Answer 41

Corticosteroid hormones (steroid hromones)

Question 42

3 classes of corticosteroids

Answer 42

1. Glucocorticoids (cortisol) 2. Mineralocorticoids (aldosterone) 3. Sex hormones (androgens and estrogens)

Question 43

Which hormones stimulates the release of the corticosteroid hormones

Answer 43

Adrenocorticotropic hormone (ACTH)

Question 44

Cortisol

Answer 44

1. Released from the adrenal cortex in response to stress and low blood glucose 2. Increases blood glucose levels and suppressing inflammatory immune responses

Question 45

Mineralcorticoids

Answer 45

Influence fluid and “mineral” or salt balance Ex. Aldosterone- promotes fluid retention by increasing sodium uptake in the distal convoluted tubule and collecting duct of the nephron

Question 46

T or F. The adrenal cortex release sex hormones in low levels in comparison to ovaries and testes

Answer 46

True

Question 47

The adrenal medulla produces which hormones?

Answer 47

Epinephrine and norepinephrine | Amino acid-derived hormones

Question 48

Pancreatic alpha cells release which hormone and what is its function?

Answer 48

Glucagon- secreted in response to low blood glucose levels | 1. Increase blood glucose levels via gluconeogenesis and glycogenolysis

Question 49

Pancreatic beta cells release which hormone and what is its function?

Answer 49

Insulin- secreted in response to high blood glucose levels | 1. Decrease glucose levels by promoting glucose uptake into body tissues

Question 50

Pancreatic delta cells release which hormone and what is its function?

Answer 50

Somatostatin (growth hormone-inhibiting hormone)- reduces stomach acid secretion and blocks the release of other digestive hormones in an effort to slow down digestion 1. Stops digestive system to digest food when there are plenty of nutrients around

Question 51

Hormone produced by muscles in the heart?

Answer 51

Atrial Natriuretic Peptide- helps regulate fluid balance (opposes aldosterone and ADH- released in response to high blood volume) 1. Decreases blood pressure by promoting fluid loss

Question 52

Hormone that helps T cells develop and mature

Answer 52

Thymosin from thymus

Question 53

3 Digestive hormones

Answer 53

Gastrin, secretin, and cholecystokinin

Question 54

This is the hormonal y active form of vitamin D and acts like the parathyroid hormone

Answer 54

Calcitriol

Question 55

Too much fluid cause (low/ high)

Answer 55

High blood pressure

Question 56

Too little fluid

Answer 56

1. Less fluid available to exert pressure on the vessel walls 2. Increase blood osmolality

Question 57

How does ADH and Aldosterone increase fluid retention and blood pressure

Answer 57

ADH: increase water absorption Aldo: promotes sodium reabsorption which drives water absorption

Question 58

T or F. T4 is 3 or 4 times more potent than T3

Answer 58

False. Opposite