[Chapter 32] Endocrine Control Flashcards

1
Q

Animal hormones

A

Cell products secreted from endocrine glands, endocrine cells, and a few neurons. In most cases, bloodstream circulates hormones to target cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Neurotransmitters

A

Secreted by neurons into the tiny synaptic cleft between a neuron and a target cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Local signaling molecules

A

Secreted by many cell types into extracellular fluid and broken down quickly; molecules only persist long enough to affect nearby tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Pheromones

A

Signals that diffuse through water or air to target cells in other individuals of the same species. Help integrate social behaviour (ex: female moth releases sex pheromone and attracts mate) Many vertabraes have vomeronasal organ in nose that responds to pheromones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

When was the word hormone first used, what is its origin, and who coined it?

A

Early 1900s by physiologists W Bayliss and E Starling, from Greek word ‘hormon’, meaning ‘to set in motion’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

List the sources vertebrate hormones are (generally) secreted from

A
pituitary gland
adrenal gland (2)
pancreatic islets (numerous cell clusters)
thyroid gland
parathyroid gland (4 in humans)
pineal gland
thymus gland
gonads (2)
endocrine cells of the hypothalamus, stomach, small intestine, liver, kidneys, heart, placenta, skin, adipose tissue, and other organs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Endocrine system

A

All sources of hormones in the animal body, linked structurally and functionally with the nervous system in intercellular communication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How is the nervous system and the endocrine system linked?

A

Share a few structures, issue a few of the same signals, most organs accept and respond to signals from both.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

In all animals, signaling molecules do what?

A

Integrate cell activities. each tupe of signal acts on all cells that have receptors for it. targeted cells may alter their activities in response.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Hypothalamus (part of the brain)

A

Produces, secretes six releasing and inhibiting hormones (act on different endocrine cells in anterior lobe of pituitary)

Produces ADH (conserves water) and oxytocin (roles in childbirth, milk secretion).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Pituitary gland, anterior lobe

A

ACTH, TSH, FSH, and LH (stimulate the secretion of other hormones), prolactine (affects mammary gland development), growth hormone (affects overall growth)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Pituitary gland, posterior lobe

A

Stores, secretes two hypothalamic hormones: ADH and oxytocin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
Adrenal gland (one pair)
Cortex
A

Cortisol (affects glucose metabolism) and aldosterone (conserves sodium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
Adrenal gland (one pair)
Medulla
A

Epinephrine and norepinephrine (these hormones interact, in conert with the supathetic nervous system, to help adjust organ activities, especially during times of excitment or stress)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Ovaries (one pair of female gonads)

A

Estrogens and progesterone (maintain primary sex organs, influence secondary sexual traits)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Testes (one pair of male gonads)

A

Testosterone (develops and maintains primary sex organs, influences secondary sexual traits)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Pineal gland

A

Melatonin (affects biological clocks, overall level of activity, reproductive cycles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Thyroid gland

A

Thyroid hormone (affects growth and development, metabolism), calcitonin (lowers blood level of calcium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Parathyroid glands (four)

A

Parathyroid hormone (increases blood level of calcium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Thymus gland

A

Thymosins (roles in white blood cell functioning)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Pancreatic islets

A

Insulin (lowers blood level of glucouse), glucagon (raises blood level of glucose)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Hormones induce changes in service of programs of…

A

Growth, maintenance, and reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Three steps of cell communication

A

Signal Reception (signal activates target cell receptor), signal transduction (transduced to a molecular form that acts in the receiving cell), cellular response (cell may make a functional response)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What do enzymes do?

A

Make hormones from a variety of sources

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Steroid hormones are derived from?

A

Cholesterol

ex: testosterone and other androgens, estrogens, progesterone, aldosterone, cortisol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Amine hormones are?

A

Modified amino acids

ex: melatonin, epinephrine, thyroid hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Peptide hormones are?

A

Short chains of amino acids

ex: glucagon, oxytocin, antidiuretic hormone, calcitonin, parathyoid hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Protein hormones are?

A

Longer chains of amino acids

ex: growth hormone, insulin, prolactin, follicle-stimulating hormone, luteinizing hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Signal response requires?

A

Functional receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Second messenger

A

A molecule that is formed in response to an external signal and causes more cellular changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What kind of things influence hormone action?

A

Type/state of target receptors, interventions by other hormones, feedback mechanisms, environmental cues, etc
More specifically…
1. Cells need the right receptors for specific hormones
2. Different hormones often interact. Binding of one hormone may block, enhance, or have no effect on the cell’s response to other hormones
3. Concentration of particular hormone in tissue. More hormone molecules in the interstitial fluid around target cell, more likely to bind with receptors
4. Target cell’s metabolic and nutritional state
5. Specific environmental cues like temperature, day length, etc

32
Q

How do hormone molecules interact with receptors on/in target cells?

A

they reversibly bind

33
Q

How do steroid and thyroid hormones bind to change gene expression?

A

With receptors insider the cell

34
Q

How do steroid and thyroid hormones bind without changing gene expression?

A

With receptors at the cell surface, triggers fast responses

35
Q

How do peptide and protein hormones bind?

A

to membrane receptors. often, second messenger in cytoplasm relays signal to cell’s interior

36
Q

Hypothalamus

A

Forebrain region, has neurons that secrete hormones

37
Q

Pituitary gland

A

Attached by a stalk of tissue to the hypothalamus. in humans, no bigger than a pea.

38
Q

Posterior lobe of pituitary gland

A

stores and secretes hormones from hypothalamus

39
Q

Anterior lobe of pituitary gland

A

Makes own hormones, signals from hypothalamus control their release

40
Q

How do the hypothalamus and the pituitary gland work together?

A

Interacts as a master control center, integrating much of the activity of the endocrine and nervous systems

41
Q

Releasers

A

Call for the secretion of hormones by target cells

42
Q

Inhibiters

A

discourage target cell secretions

43
Q

ACTH

A

stimulates the release of cortisol from a pair of adrenal glands

44
Q

TSH

A

stimulates the release of thyroid hormones from the thyroid gland

45
Q

FSH and LH

A

affect gamete formation in the reproductive organs and other aspects of sexual reproduction

46
Q

GH

A

growth hormone, has targets in most tissues. triggers secretions from liver cells that promote growth of bone and soft tissues in the young, influences metabolism in adults

47
Q

PRL

A

initiates and maintains milk production in mammary glands after other hormones prime the tissues

48
Q

Thyroid Gland

A

Anterior base of the beck, secretes calcitonin and thyroid hormone, which is a ix of two amines

49
Q

Thyroid hormone

A

Central to metabolism and development

50
Q

How is the thyroid gland controled?

A

By the anterior pituitary and hypothalamus, through negative feedback loops

51
Q

Parathyroid glands

A

Four of them on the posterior surface of the thyroid, secrete PTH. Main control over the calcium in blood

52
Q

PTH

A

parathyroid hormone, stimulates the breakdown of bone, decreases calcium loss in urine, and activates the vitamin D needed to absorb calcium from food.

53
Q

Vitamin D and PTH

A

PTH activates vitamin D needed to absorb calcium from food, thus, PTH increases blood calcium. Vitamin D deficiency lowers calcium level in blood, which leads to oversecretion of PTH and bone breakdown

54
Q

Adrenal Glands

A

Humans have a pair of adrenal glands, one on top of each kidney.

55
Q

Adrenal cortex

A

Outermost part of adrenal glands, releases steroid hormones

56
Q

Aldosterone

A

Controls sodium and water reabsorption in the kidneys, released by adrenal glands

57
Q

Cortisol

A

Released by adrenal glands, affects metabolism and immune responses, maintains blood level of glucose, induces liver cells to break down their store of glycogen, supresses uptake of glucose by other cells. induces adipose cells to degrade other fats, and skeletal muscles to degrade proteins, makes immune responses wind down. controled by negative feedback loop

58
Q

When and by what is the cortisol feedback loop overridden?

A

The nervous system overrides it during times of injury, illness, anxiety. this leads to very high levels of cortisol

59
Q

Adrenal medulla

A

Inner part of adrenal gland, secretes norepinephrine and epinephrine during times of stress, excitement, or danger.

60
Q

Norepinephrine and epinephrine

A

Same effects on targets that sumpathetic nerves do, bring about fight-or-flight response

61
Q

Long term elevation of cortisol levels?

A

Disrupts production and release of other hormones, suppress immune function, impair memory. impact can be seen in people with Cushing syndrome

62
Q

Pancreas

A

in abdominal cavity behind the stomach, has exocrine (scretes digestive enzymes into duct to small intestine) and endocrine functions (clusters called pancreatic islets, contains three types of hormone-secreting cells)

63
Q

Alpha cells

A

Secrete the peptide hormone glucagon. between meals, all cells take up glucose from blood. When glucose level falls below set point, alpha cells secrete glucagon, which binds cells int he liver and causes activation of enzymes that break glycogen into glucose subunits. Raises level of glucose in the blood

64
Q

Beta cells

A

Most abundant cells in pancreatic islets, secrete insulin, the only hormone that causes target cells to take up and store glucose. Releases insulin after stimulated by higher blood level of glucose

65
Q

Delta cells

A

Secretes somatostatin, helps control digestion and nutrient absorbtion. Can inhibit the secretion of insulin and glucagon

66
Q

Diabetes mellitus

A

Metabolic disorder in which cells do not take up glucose as they should, in result, sugar accumulates in blood and urine. This encourages growth of pathogenic bacteria, damages small blood ells in kidneys, permanent kidney failure. Uncontrolled diabetes also damages blood vessels and nerves, especially in arms, hands, legs, and feet

67
Q

Type I Diabetes

A

Develops after the body has mounted an autoimmune response against is insulin-secreting beta cells. Most dangerous type of diabetes short term. In absence of glucose, the body uses fats and proteins as energy sources. Two outcomes are weight loss and ketone accumulation in the blood and urine. Can interfere with brain funtion, extreme causes may lead to coma or death

68
Q

Type II Diabetes

A

More common form of disorder. Insulin levels are normal or high but target cells do not respond to the hormone as they should and blood sugar levels remain high. If glucose lvels are not lowered, pancreatic beta cells continue to receive continual stimulation and they will eventually falter

69
Q

Hypoglycemia

A

Blood glucose level falls low enough to disrupt normal body functions. Rare insulin-secreting tumours can cause it, but usually after insulin-dependent diabetic miscalculates and injects too much insulin to balance food intake. Results in insulin shock, brain stalls as its fuel dwindles. Can be lethal, but injection of glucagon reverses condition

70
Q

Gonads

A

Male = testes, females = ovaries. produces gametes and secrete sex hormones, including estrogens and androgens

71
Q

Puberty

A

Post-embyronic stage of development when the reproductive organs and structures mature

72
Q

Estrogen in males

A

Develops sperm

73
Q

Testosterone in females

A

Affects libido

74
Q

Pineal Gland

A

Depp inside the vertabrate brain. Secretes melatonin, which serves as part of internal timing (biological clock, rate of secretion varies depending on amount of light brain is responding to.

75
Q

Thymus gland

A

Lies beneath breastbone, secretes hormones that help infection-fighting white blood cells (T cells) to mature, grows until person reaches puberty, when the surge in sex hormones causes it to shrink and its secretions decline

76
Q

How did vertabrates evolve so many diverse hormones and hormone receptors?

A

Molecular evidence points to gene duplications and subsequent divergences through mutations

77
Q

Ecdysone

A

Steroid hormone, controls molting in nematodes and arthropods, influences by environmental cues