Endocrinology Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

endocrine system

A

acts as means of internal communication, coordinating the activities of organ systems

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

hormones

A

chemical substances synthesized and secreted by endocrine glands directly into the circulatory system.

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

Exocrine glands

A

secrete substances that are transported by ducts

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

two chemical structures of hormones

A

peptide hormones and steroid hormones.

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

Peptide hormones

A

act as first messengers binding to specific extracellular receptors on the surface of their target cells, they rigger a series of enzymatic reactions within the cell. causing a cascade effect usually fast acting and short lived

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

Cyclic AMP

A

acts a second messenger from the enzymatic conversion of ATP, which was catalyzed by membrane bound enzyme adenylate cyclase.
it relays messages from the extracellular peptide hormone enzymes.
-inactivated by cytoplasmic enzyme phosphodieterase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Steroids hormones

A
belong to a class of lipid derived molecules, because the are lipid soluble, steroid hormones enter their target cells directly and bind to intracellular receptor proteins in cytoplasm
-this complex enter the nucleus and directly activates expression. longer and longer effect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

endocrine glands

A

pituitary, hypothalamus, thyroid, parathyroid, adrenals, pancreas, testes, ovaries, pineal, kidneys, gastrointestinal glands, heart and thymus

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

adrenal glands

A

are situated on top of the kidneys and consist of the adrenal cortex and adrenal medulla

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

adrenal cortex

A

in response to stress ATCH stimulates the adrenal cortex to synthesize and secrete the steroid hormones which are collectively known as corticosteroids.

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

corticosteroids

A

derived from cholesterol include glucocorticoids, mineralcorticoids and cortical sex hormones.

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

glucocorticoids

A

cortisol and cortisone, involved in glucose regulation and protein metabolism. Rasing blood glucose levels by promoting protein breakdown and using the products in gluconeogenesis. also raises the plasma glucose levels and decreases protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

gluconeogenesis

A

a metabolic pathway that generates glucose from non carbohydrates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

mineralcorticoids

A

particularly aldosterone regulates plasma levels of sodium and potassium and the total extracellular water volume.

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

aldosterone

A

causes active re-absorption of sodium and passive re-absorption of water in the nephron. results in the rise in both blood volume and blood pressure. this excess retention leads to hypertension

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

corical sex hormones

A

the adrenal cortex secretes small quantities fo androgens (male hormones) like androstendione and dehydropieandrosterone in males and females. has no real effect in males due to its already present. but over production in females leads to masculinizing effects

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

adrenal medulla

A

produces epinephrine and norepinephrine both of which belong to a class of amino acid derived compounds called catecholamines

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

epinephrine

A

increases the conversion of glycogen to glucose in liver and muscle tissue, causing a rise in blood glucose levels and increase in basal metabolic rate. along with norepinephrine it increases the strength of the heart beat to assist in “fight or flight”

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

control of adrenal hormones

A

release of adrenal cortical hormones is under the control of ACTH, aldosterone is controlled by renin angiotensisn mechanism.

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

Pituitary gland

A

(hypophysis) small trilobed gland lying at the base of the brain. the two main lobes, anterior and posterior are functionally distinct.

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

anterior pituitary

A

synthesizes both direct and tropic hormones. the hormonal secretions of this portion of the pituitary is regulated by hypothalamic secretion called releasing and inhibiting hormones or factors.

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

direct hormones

A

anterior pituitary hormones that directly synthesize their target organs. (PEG) prolactin, endorphins, growth hormone

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

Growth Hormone

A

GH (somatotrophin) promotes the bone and muscle growth

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

acromegaly

A

a disorder caused from GH over production in humans that have disproportionate over growth

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

prolactin

A

stimulates mile production and secretion in female mammary glands.

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

endorphins

A

neurotransmitters that behave like opoids, providing internal pain relief and production of pleasure sensations

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

Tropic hormones

A

from the anterior pituitary, which stimulate other endocrine glands to release hormones. (FLAT) follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, adrenocorticotropic hormone

28
Q

ACTH

A

adrenocorticotropic hormone stimulates the adrenal cortex to synthesize and secrete glucocorticoids and is regulated by the releasing hormone CRF

29
Q

TSH

A

thyroid stimulating hormone- stimulates the thyroid gland to synthesize and release thyroid hormones

30
Q

LH

A

lutenizing hormone- in females LH stimulates ovulation and formation of the corpus luteum. in males LH stimulates the interstitial cells of the testes to synthesize testosterone.

31
Q

corpus luteum secretes

A

progesterone and estrogen

32
Q

FSH

A

follicle stimulation hormone- in females causes maturation of ovarian follicles which secrete estrogren. in males it stimulates maturation of the seminiferous tubules and sperm production.

33
Q

Posterior pituitary

A

neurohypophysis) does not synthesize hormones its stores and releases the peptide hormones oxytocin and ADH which is produced by the hypothalamus. secretion occurs when action potentials descend from the hypothalamus

34
Q

Oxytocin

A

secreted during child birth, increases the strength and frequency of uterine muscle contractions. Oxytocin release causes uterine contractions and uterine contractions stimulates oxytocin release. also induced by suckling as it also stimulates milk in the mammary glands.

35
Q

ADH

A

anti duiretic hormone or vasopressin. increases the permeability of the collecting duct of the nephron (in kidney) to water. which promotes water absorption and increases blood volume. sensed by baroreceptors in the circulatory system.

36
Q

Hypothalamus

A

part of the forebrain and is located directly above the pituitary gland. receives neural transmissions from other parts of the brain and peripheral nerves from its neurosecretory cells.

37
Q

how do neurosecretary cells regulate pituitary secretions

A

via negative feedback mechanisms and through actions of inhibiting and releasing hormones.

38
Q

hypothalamic interaction with the anterior pituitary

A

the hypothalamic releasing hormones stimulate or inhibit the secretions of the anterior pituitary. Releasing hormones are secreted into the hypothalamic-hypophyseal protal system. this way releasing hormones can immediately reach the anterior pituitary.

39
Q

hypothalamic interactions with posterior pituitary

A

neurosecretory cells in the hypothalamus synthesize both oxytocin and ADH and transport them via their axons into the posterior pituitary for storage and secretion.

40
Q

thyroid

A

the thyroid gland is a bi-lobed structure located on the ventral surface of the trachea. It produces secretes thyroxine and triiodothyronine and calcitonin

41
Q

thyroid hormones

A

thyroxine (t4) and triiodothyronine (T3) are derived from the iodination of the amino acid tyrosine. they are necessary for growth and neurological development of children. they also increase the rate of metabolism. malfunctions cause goiters.

42
Q

hypothyroidism

A

thyroid hormones are undersecreted or secreted at all. symptoms include slowed heart rate, and respiratory rate, fatigue, cold intolerance and weight gain.

43
Q

hyperthyroidism

A

thyroid is over stimulated, resulting in the over secretion of thyroid hormones. symptoms are increased metabolic rate, excessive warmth, profuse sweating, palpation, weight loss and protruding eyes.

44
Q

calcitonin

A

decreases plasma Ca2+ concentration by inhibiting the release of Ca2+ from bone. Calcitonin is regulated by Ca+ levels. antagonistic to parathyroid hormone.

45
Q

Pancreas

A

both an exocrine and endocrine organ. exocrine function performed by cells that secrete digestive enzymes into the SI. the endocrine is performed by small glandular structures called islets of langerhans which is composed of beta and alpha cells.

46
Q

Glucagon

A

produced by the alpha cells of the pancreas, stimulates protein and fat degradation, the conversion of glycogen to glucose and gluconeogenesis, all serving to increase blood glucose levels.

47
Q

Insulin

A

produced by the beta cell of the pancreas. a protein hormone secreted in response to high levels of glucose in the blood. stimulates the uptake of glucose by muscle and adipose cells and the storage of glucose and glycogen. to lower blood glucose levels.

48
Q

diebetes mellitus

A

under production of insulin or insensitivity to insulin that leads to hyperglycemia

49
Q

parathyroid glands

A

four small pea-shaped structures embedded in the posterior surface of the thyroid. that synthesize and secrete parathyroid hormone

50
Q

PTH

A

parathyroid hormone raises the CA2+ concentration in the blood by increasing bone re-absorption and decreasing Ca2+ excretion in the kidneys.

51
Q

Kidneys

A

when blood volume falls the kidney produces renin. which leads to the release of aldosterone from the adreanal cortex.

52
Q

Renin

A

an enzyme that converts the plasma protein andiotensinogen to andiotensin I. angiotensin I is converted to angiotensin II which stimulates the adreanal cortex.

53
Q

Gastrointestinal hormones

A
  • Ingested food stimulates gastrin. Gastrin stimulates the glands to secrete HCl.
  • secretin is released by the small intestine stimulating pancreatic fluids which neutralize the acidity of the acidic chyme.
  • cholecystokinin is released from the SI in response to fats
54
Q

cholecystokinin

A

causes the contraction of the gall bladder and realeas of bile into the small intestine. it also travels to the brain’s satiation center to indicate a full sensation

55
Q

pineal gland

A

tiny structure at the base of the brain that secretes the hormone melatonin. role of melatonin is unclear but believed to play a role in light and dark rhythms. in primitive vertebrates it lightens the skin by concentrating pigment.

56
Q

plant hormones

A

they are primarily involved in the regulation of growth. produced by actively growing parts of plant.

57
Q

auxins

A

an important class of plant hormones associated with several types of growth patterns

58
Q

Phototrophism

A

the tendency of the shoots of plants to bend towards light sources (sun). When light strikes the tip of the plant from one side the auxin supply on that side is reduced. thus the illuminated side grows slower than the shaded side.

59
Q

geotrophism

A

the growth of portions of plants towards or away from gravity

60
Q

negative geotropism

A

causes shoots to grow upward away from the acceleration of gravity. gravity increases the concentration of auxin on the lower side of a horizontally placed plant.

61
Q

positive geotropism

A

causes roots t grow towards the pull of gravity. cells exposed to a higher concentration of auxin are inhibited from growing, while cells with lower concentration continue to grow. Causing the root to go down.

62
Q

gibberellins

A

stimulate the rapid stem elongation, particularly in plants that do not grow tall. they inhibit the formation of new roots and stimulate the production of new pholem cells by cambium.
-terminate the dormacy of seeds and buds

63
Q

kinins

A

promote cell division. Kinetin is an important type of cytokinin. The ratio of kinetin to auxin is of particular importance in the determination of the timing of differentiation of new cells. action of kinetin is enhanced when auxin is present

64
Q

ethylene

A

stimulates fruit ripening. ethylene also induces senescence of aging

65
Q

inhibitors

A

block cell division and serve an important role in growth regulation. important to the maintenance of dormancy in the lateral buds and seed of plants.

66
Q

abscisic acid

A

is one of the most important inhibitors

67
Q

anit auxins

A

regulate the activity of auxins