Metabolism - 4

Question 1

What is the primary aim of the endocrine system?

Answer 1

To maintain a stable and balanced internal environment (homeostasis)

Question 2

T/F: the nervous and endocrine system act together to coordinate and regulate all systems of the body

Answer 2

True

Question 3

T/F: the nervous system releases neurotransmitters and has slow responses

Answer 3

False, has fast responses

Question 4

The endocrine system releases hormones, do they act slow or fast?

Answer 4

Slow, they going into the blood stream or the interstitial fluid and have to travel around the body

Question 5

Definition:

Exocrine glands

Answer 5

Secrete the products they produce into ducts, which are then expelled on the outside of the body

Question 6

Do exocrine glands secrete hormones?

Answer 6

No

Question 7

What are some examples of exocrine glands?

Answer 7

• sudoriferous (sweat) glands
• sebaceous (oil) glands
• muscous glands
• digestive glands

Question 8

What is the difference between signals sent in the nervous system vs the endocrin system?

Answer 8

Nervous - send neurotransmitters
Endrocrine - send hormones

Question 9

What are hormones released into?

Answer 9

The bloodstream

Question 10

What do hormones determine?

Answer 10

• the devlopment of sexual characteristics in puberty
• regulate how the body grows and develops
• how the body controls fluid, salt and sugar levels in the blood

Question 11

Definition:

Hormones that travel in blood and act on distant target cells

Answer 11

Endocrines (circulating hormones)

Question 12

Definition:

Paracrines

Answer 12

Hormones that act on neighboring cells

Question 13

Definition:

Hormones that act on the same cell that secreted them

Answer 13

Autocrines

Question 14

Hormones can be —- soluble or —- soluble?

Answer 14

Water or lipid

Question 15

Examples of lipid soluble hormones

Answer 15

• steroid hormones
• thyroid hormones
• nitric oxide

Question 16

How do lipid soluble hormones work?

Answer 16

• circulate bound to trasnport proteins
• diffuse across the plasma membrane
• bind to receptors within target cells
• activate genes to allow ribosomes to synthesize specific proteins (goes into nucleus)

Question 17

Examples of water-soluble hormones

Answer 17

• amine hormones
• peptide and protein hormones
• eicosanoid hormones

Question 18

How do water soluble hormones work?

Answer 18

• circulate freely in plasma
• bind to recpetors on the xterior surface of the target cell
• activate a secondary messenger to phosphorylate cellular proteins

Question 19

Phosphorylation can either:

Answer 19

• activate (excitatory) –> results in the production of proteins through a chain reaction
• inactivate (inhibitory)

Question 20

T/F: hormone regulation can also be controlled through alterations to the receptors themselves

Answer 20

True

Question 21

Definition:

Up-regulation

Answer 21

Receptors become more sensitive (more receptors) in the presence of low concentrations of hormone

Question 22

Definition:

Receptors become less sensitive (less receptors) in the presence of high concentrations of hormone

Answer 22

Down-regulation

Question 23

What is the response of a target cell to a hormone based on?

Answer 23

• hormones concentration in the blood
• number of hormone receptors on the target cell
• influences exerted by other hormones

Question 24

Definition

Synergistic effect

Answer 24

Some hormones work more effectively when a second hormone is present to assist them

Question 25

# Definition Antagonistic effect

Answer 25

some hormones oppose the action of others

Question 26

Go over norepinepherine responses (slide 20)

Question 27

Why are hormones released in short bursts?

Answer 27

To maintain homeostasis and prevent over or underproduction of a particular hormone

Question 28

What is hormone secretion regulated by?

Answer 28

- Chemical changes in the blood - signals from the nervous system - other hromones

Question 29

T/F: most endocrine glands are under positive feedback control that acts to maintain homeostasis

Answer 29

False, negative feedback loops

Question 31

What is the major regulatory role of the hypothalamus?

Answer 31

Regulates homeostasis for body temperature, blood glucose levels and osmotic pressure

Question 32

T/F: the hypothalamus is the main link between the endocrine and the nervous system

Answer 32

true

Question 33

How many hormones does the hypothalamus release?

Answer 33

7

Question 34

Hormones released from the hypothalamus instruct which gland to release certain hormones?

Answer 34

The pituitary gland

Question 35

List the releasing hormones of the hypothalamus.

Answer 35

- thyrotropin releasing hormone (TRH) - corticotropin releasing hormone (CRH) - gonadotropin releasing hormone (GnRH) - Prolactin releasing hormone (PRH) - growth hormone releasing hormone (GHRH) -- somatocrinin

Question 36

List the inhibiting hormones of the hypothalamus.

Answer 36

- growth hormone inhibiting hormone (GHIH) -- somatostatin - prolactin inhibiting hormone (PIH) -- dopamine

Question 37

What connects the hypothalamus and the pituitary gland?

Answer 37

Infundibulum (stalk)

Question 38

How do the hormones released by the hypothalamus reach the pituitary gland?

Answer 38

Via the hypophyseal portal system (circulation from hypothalamus goes directly to pituitary gland, so it does not enter systemic circulation)

Question 39

What part of the pituitary gland makes up 75% of its weight?

Answer 39

The anterior Lobe (adenohypophysis)

Question 40

How many types of cells are located in the anterior pituitary gland and how many hormones do they secrete?

Answer 40

cells - 5 hormones - 7

Question 41

What are the 7 hormones released by the anterior pituitary gland?

Answer 41

1. human growth hormone (hGH) 2. Prolactin (PRL) 3. Thyroid-stimulating hormone (TSH) 4. Follicle stimulating hormone (FSH) 5. Luteinizing hormone (LH) 6. andrenocoticotrophic hormone (ACTH) 7. melanocyte-stimulating hormone (MSH)

Question 42

What cells secrete hGH?

Answer 42

somatrophs

Question 43

What cells secrete PRL?

Answer 43

lactrotrophs

Question 44

What cells secrete TSH?

Answer 44

Thyrotrophs

Question 45

What cells secrete FSH and LH?

Answer 45

Gonadotrophs

Question 46

What cells secrete ACTH and MSH?

Answer 46

Corticotrophs

Question 47

What is the most plentiful anterior pituitary hormone that aids with the growth of bones and muscles?

Answer 47

Human growth hormone (hGH)

Question 48

What 2 hypothalamic hormones control the release of hGH?

Answer 48

- GHRH - GHIH

Question 49

# Definition: Stimulates the production of thyroid hormones from the thyroid gland activities and is controlled by TRH (thyrotropin relaeasing hormone)

Answer 49

TSH (thyroid stimulating hormone)

Question 50

# Definition: PRL

Answer 50

With other hormones, initiates and maintaines milk secretion by the mammary glands

Question 51

What does FSH do in females?

Answer 51

initiates follicle development and secretion of estrogens in ovaries

Question 52

What does FSH do in males?

Answer 52

Stimulates sperm production in the testes

Question 53

# Definition: Controls the production and secretiopn of hormones called glucocorticoids by the cortext of the adrenal gland.

Answer 53

ACTH (adrenocorticotrophic hormone)

Question 54

What is the posterior lobe (neurohypophysis) of the pituitary gland made of?

Answer 54

Neural tissue

Question 55

Which is more vascularized, anterior or posterior pituitary gland?

Answer 55

anterior

Question 56

T/F: posterior pituitary gland synthesizes hormones

Answer 56

false! It only stores and relases 2 hormones that are synthesized in the hypothalamus

Question 57

What 2 hormones are stored in the posterior pituitary gland?

Answer 57

Oxytocin and ADH (anti-diruetic hormone)

Question 58

# Definition: Released in repsonse to stretch placed on the cervix during child birth

Answer 58

Oxytocin

Question 59

Does oxytocin work through a + or - feedback loop?

Answer 59

Positive!

Question 60

What does oxytocin affect?

Answer 60

- uterus: enhances contractions - breasts: stimulates milk production by the mammary glands in response to suckling - males: aids in the dopamin-oxytocin-nitric oxide pathway for erections

Question 61

What does the amount of ADH produced vary with?

Answer 61

Blood osmotic pressure

Question 62

Explain how ADH works.

Answer 62

ADH decreases urin output as part of a - feedback loop where osmoreceptors in the hypothalamus monitor blood osmotic pressure

Question 63

An increase in blood volume cause a ____ in ADH secretion.

Answer 63

decrease

Question 64

An decrease in blood volume cause a ____ in ADH secretion.

Answer 64

increase