Endocrine part 1

Question 1

What is the endocrine system?

Answer 1

A network of glands that produce and release hormones to regulate bodily functions, including metabolism, growth, development, reproduction, and homeostasis.

Question 2

What is a hormone?

Answer 2

Chemical messengers secreted by cells into the extracellular fluids that regulate the metabolic function of other cells.

Question 3

List three functions of the endocrine system.

Answer 3

• Maintains homeostasis
• Controls growth and development
• Regulates metabolism and energy balance

Question 4

Compare the response time of the endocrine system to the nervous system.

Answer 4

Endocrine system initiates responses slowly; nervous system initiates responses rapidly.

Question 5

What are exocrine glands?

Answer 5

Glands that produce nonhormonal substances and have ducts that carry these substances to a membrane surface.

Question 6

What are the two types of glands in the endocrine system?

Answer 6

• Exocrine glands
• Endocrine glands (ductless)

Question 7

Name two examples of amino acid-based hormones.

Answer 7

• Epinephrine
• Thyroxine

Question 8

What are eicosanoids?

Answer 8

Signaling molecules that include leukotrienes and prostaglandins, affecting nearby cells.

Question 9

True or False: Steroid hormones are synthesized from cholesterol.

Answer 9

True

Question 10

What is the role of target cells?

Answer 10

Specific cells that respond to hormones, neurotransmitters, or other signaling molecules by containing receptors that bind these molecules.

Question 11

Fill in the blank: Hormones travel through the blood but only affect _______.

Answer 11

target cells

Question 12

List two types of hormone actions.

Answer 12

• Open or close ion channels
• Stimulate protein synthesis

Question 13

What mechanism do water-soluble hormones use to act on target cells?

Answer 13

They act on receptors in the plasma membrane, often coupled via G proteins to intracellular second messengers.

Question 14

What is permissiveness in hormone interactions?

Answer 14

A situation in which one hormone cannot exert its full effects without another hormone being present.

Question 15

What is the function of oxytocin?

Answer 15

Stimulates uterine contractions during childbirth and milk ejection in nursing women.

Question 16

What is the primary function of the adrenal cortex?

Answer 16

Regulates sodium and potassium balance, increases blood sugar, and produces sex hormone precursors.

Question 17

What is the role of insulin?

Answer 17

Lowers blood glucose levels.

Question 18

What type of hormone is testosterone?

Answer 18

Steroid hormone

Question 19

What does the hypothalamus secrete to stimulate the pituitary gland?

Answer 19

Releasing hormones (e.g., CRH, TRH, GnRH, GHRH)

Question 20

What is the function of parathyroid hormone (PTH)?

Answer 20

Increases blood calcium levels.

Question 21

Describe the cyclic AMP mechanism.

Answer 21

Hormone binds to membrane receptor, activates G protein, which activates adenylate cyclase to generate cAMP, stimulating protein kinase reactions.

Question 22

What does the term ‘antagonism’ refer to in hormone interactions?

Answer 22

When one hormone opposes the action of another.

Question 23

What is the role of the adenohypophysis?

Answer 23

The glandular part of the pituitary gland that manufactures and releases hormones.

Question 24

What hormone does the anterior pituitary release that stimulates growth?

Answer 24

Growth Hormone (GH)

Question 25

What is the primary effect of cortisol?

Answer 25

Increases blood sugar and suppresses inflammation.

Question 26

What does the term 'neuroendocrine integration' refer to?

Answer 26

The coordination between the nervous system and endocrine system for body regulation.

Question 27

Fill in the blank: Hormones that act on receptors inside the cell are classified as _______.

Answer 27

lipid-soluble hormones

Question 28

What is the effect of aldosterone?

Answer 28

Regulates sodium and potassium balance.

Question 29

What triggers the release of hormones in the humoral mode?

Answer 29

Altered levels of certain critical ions or nutrients.

Question 30

What is the primary function of glucagon?

Answer 30

Raises blood glucose levels.

Question 31

What does the term 'synergism' mean in hormone interactions?

Answer 31

When more than one hormone produces the same effects at the target cell and their combined effects are amplified.

Question 32

True or False: Eicosanoids fit the definition of true hormones.

Answer 32

False

Question 33

What is the function of melatonin?

Answer 33

Regulates sleep-wake cycles.

Question 34

What is the function of thyrotropin (TSH)?

Answer 34

Stimulates development of and secretion from the thyroid gland ## Footnote TSH is a tropic hormone that follows the hypothalamic–pituitary–target endocrine organ feedback loop.

Question 35

What initiates the release of TSH?

Answer 35

Hypothalamus secretes TRH ## Footnote TRH causes thyrotrope cells of the anterior pituitary to produce TSH.

Question 36

What happens to TSH levels when they increase?

Answer 36

Inhibit both pituitary gland and hypothalamus ## Footnote Increased TSH levels also stimulate production of GHIH.

Question 37

What is the primary function of Adrenocorticotropic Hormone (ACTH)?

Answer 37

Stimulates adrenal cortex to release corticosteroid hormones ## Footnote Especially glucocorticoids.

Question 38

From what precursor molecule is ACTH derived?

Answer 38

Pro-opiomelanocortin (POMC) ## Footnote POMC is a large precursor molecule from which ACTH is split.

Question 39

What stimulates the release of ACTH?

Answer 39

Hypothalamus secretes CRH ## Footnote CRH stimulates corticotrope cells to release ACTH.

Question 40

What stops the secretion of ACTH?

Answer 40

Increased levels of glucocorticoids ## Footnote Fever, hypoglycemia, and stressors promote CRH release.

Question 41

What are gonadotropins?

Answer 41

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) ## Footnote They regulate the function of the gonads (ovaries and testes).

Question 42

What is the role of FSH in males?

Answer 42

Stimulates sperm production ## Footnote LH stimulates the interstitial cells of the testes to produce testosterone.

Question 43

What is the role of LH in females?

Answer 43

Triggers ovulation and promotes synthesis and release of ovarian hormones ## Footnote Works with FSH to cause an egg-containing ovarian follicle to mature.

Question 44

How does the gonadotropin cascade begin?

Answer 44

At puberty, hypothalamus secretes GnRH ## Footnote GnRH stimulates gonadotrope cells to secrete gonadotropins.

Question 45

What is the main function of prolactin?

Answer 45

Stimulates milk production by the breasts ## Footnote Prolactin’s only well-documented effect in humans.

Question 46

What initiates prolactin release?

Answer 46

High estrogen levels ## Footnote Estrogen stimulates lactotropes to secrete prolactin by suppressing PIH production.

Question 47

What happens to prolactin production when estrogen levels decrease?

Answer 47

Prolactin production stops ## Footnote Decreased estrogen stimulates production of PIH from the hypothalamus.

Question 48

What maintains prolactin production during breastfeeding?

Answer 48

Suckling ## Footnote Lack of suckling and return of normal hormonal cycles brings about PIH production.

Question 49

Fill in the blank: ACTH is secreted by the _______.

Answer 49

Anterior pituitary

Question 50

True or False: FSH is responsible for stimulating the production of testosterone in males.

Answer 50

False ## Footnote LH is responsible for stimulating testosterone production in males.