Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

VET 410: Endocrinology > Hormone & Receptor Physiology > Flashcards

Hormone & Receptor Physiology Flashcards

1
Q

functions of the endocrine system

A
  1. maintain homeostasis
  2. coordinate growth and development
  3. regulate sexual reproduction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

homeostasis

A

the maintenance of steady states in an animal by coordinate physiological processes or feedback mechanisms

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

what effect do endocrine diseases have on hormone production

A

increase, decrease, or no change

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

what are the endocrine glands

A
  1. pituitary
  2. thyroid
  3. parathyroid
  4. adrenals
  5. pineal
  6. testes/ovaries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are exocrine glands that have an endocrine component

A

kidneys, pancreas

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

where tissues have endocrine cells scattered throughout

A

GI tract, heart, kidney, liver, adipose tissue

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

function of endocrine glands

A

responsible for the regulated secretion of chemical messengers (hormones) into systemic circulation

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

how to hormones enter circulation

A

via fenestrated capillaries

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

hormones

A

chemical which affects target cells or organs via transport in the bloodstream

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

what does the response of a cell depend on

A
  • hormone concentration
  • number of receptors
  • binding strength
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

do hormones create new reactions within a cell

A

NO - modulate reactions already occurring in the cell

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

what concentration are hormones present in circulation

A

low concentrations

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

negative physiological response driven feedback loop

A

the physiological response of the body to the release of a hormone will inhibit further release of that hormone

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

positive physiological response driven feedback loop

A

the physiological response of the body to the release of a hormone will stimulate further release of that hormone

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

negative endocrine axis driven feedback loops

A

the release of a hormone stimulates the release of more hormones from different endocrine glands, and the response of the body to those hormones will result in inhibition of the axis

ex. hypothalamic-pituitary-adrenal axis

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

what controls the level of hormones in the body

A
  1. biosynthesis
  2. precursor processing
  3. hormonal release
  4. protein binding
  5. metabolic clearance
  6. feedback loops
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the types of hormones

A
  1. peptides/proteins
  2. amino acid derivatives (catecholamines, thyroid hormones)
  3. steroid hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

polarity, protein binding, half life, and receptor type of peptide/protein hormones

A
  • polar (water soluble)
  • non protein bound
  • short half life
  • cell surface receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

metabolism/clearance, biosynthesis, and release of peptide/protein hormones

A
  • endocytosis and enzymatic degradation
  • protein synthesis (DNA to RNA to mRNA to preprohormone to prohormone to hormone)
  • storage in membrane bound vesicles OR immediate release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

examples of peptide/protein hormones

A

POMC

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

what amino acid are catecholamines and thyroid hormones derived from

A

tyrosine

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

polarity, protein binding, half life, and receptor type of catecholamines

A
  • polar
  • non protein bound OR loosely albumin bound
  • short half life
  • cell surface receptor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

metabolism/clearance, biosynthesis, and release of catecholamines

A
  • enzymatic degradation and endocytosis
  • enzyme modifications of tyrosine
  • stored in secretory vesicles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

examples of catecholamines

A

epinephrine, norepinephrines

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

polarity, protein binding, half life, and receptor type of thyroid hormones

A
  • non polar
  • highly protein bound
  • long half life
  • intracellular receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

metabolism/clearance, biosynthesis, and release of thyroid hormones

A
  • inactivated by deiodination and phase II metabolism
  • iodide + AA uptake into follicular lumen, iodination of tyrosine residues on thyroglobulin, coupling of iodinated residues, release of T3/T4 from thyroglobulin
  • storage in colloid of follicular lumen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

examples of thyroid hormones

A

T3 (active)
T4 (inactive)

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

categories of steroid hormones

A

progestins: progesterone
mineralocorticoids: aldosterone
glucocorticoids: cortisol
androgens: testosterone
estrogens: estrogen

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

polarity, protein binding, half life, and receptor type of steroid hormones

A
  • non polar
  • highly protein bound
  • variable half life
  • intracellular receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

metabolism/clearance, biosynthesis, and release of steroid hormones

A
  • metabolized in liver to inactivate, excreted in urine after phase I and II metabolism
  • enzymatic modification of cholesterol (steroid hydroxylase, dehydrogenase)
  • NO storage - produced and released as needed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

hormone receptors

A

bind specific hormones with high affinity and specificity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what are the types of intracellular receptors

A

cytosolic
nuclear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what are the types of cell surface receptors

A

GPCRS (seven transmembrane)
single transmembrane (growth factor, cytokine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

signal transduction

A

a pathway of events by which each component participates in the process of transmitting a signal to the target molecular within the cell

hormone –> receptor –> signal mediator –> target molecule –> response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what are the ligands for cell surface receptors

A

water soluble hormones (peptides/proteins, catecholamines)

36
Q

what are the methods of signal transduction of cell surface receptors

A

growth factor: protein activity (kinase/phosphatase), ion movement

cytokine: transcriptional modification

37
Q

G-protein coupled receptors (GPCRs)

A

seven transmembrane receptors (cross the membrane 7x)

subtypes: Gi, Gq, Gs, G12

38
Q

single transmembrane receptors

A

only cross the membrane one time

growth factor receptors and cytokine receptors

39
Q

growth factor receptors

A

extracellular binding site + intracellular tyrosine kinase domain

  1. hormone binding induces conformational change
  2. autophosphorylation of tyrosine residues on kinase
  3. recruits secondary effector protein
  4. signal cascade
40
Q

cytokine receptors

A
  1. hormone binds
  2. recruits effector protein
  3. autophosphorylation of kinase
  4. recruits secondary effector protein
  5. receptor dimerizes
  6. signal cascade
41
Q

what are the ligands for intracellular receptors

A

lipid soluble hormones (thyroid and steroid hormones)

42
Q

what are the methods of signal transduction of intracellular receptors

A

transcriptional regulation by binding directly to DNA

43
Q

subregions of intracellular receptors

A
  1. activation region - ligand-independent activation
  2. DNA binding - binds to specific DNA sequence, dimerization
  3. ligand binding - site of ligand binding, hetero/homodimerization
  4. coactivator/repressor - site of regulatory factor binding
44
Q

location and ligands used by cytosolic receptors

A

receptor located in the cytosol

used by steroid hormones (glucocorticoid, mineralocorticoid, androgen, and progesterone receptors)

45
Q

mechanism of cytosolic receptors

A
  1. ligand binding releases repressor (heat shock protein)
  2. induces homodimerization of receptor
  3. receptor-ligand complex binds to DNA sequence (HRE) to alter transcription
46
Q

location and ligands of nuclear receptors

A

receptor located already bound to DNA sequence

used by thyroid hormones and estrogen

47
Q

mechanism of nuclear receptors

A
  1. ligand enters directly into nucleus and binds receptor already bound to DNA segment
  2. releases repressor (NOT heat shock protein except estrogen)
  3. induces heterodimerization
  4. regulates gene transcription
48
Q

features of endocrine glands

A
  • ductless
  • highly vascularized
  • contain secretory cells (cords, single cells, clusters, or follicles)
  • prominent nuclei, mitochondria, ER, golgi, secretory vesicles
  • store or secrete hormones directly
49
Q

pituitary gland

A

down growth of neural tissue from the hypothalamus

site of diverse hormone production BUT each cell type only produces one hormone

50
Q

pituitary hormone function

A
  1. act directly on non-endocrine tissues
  2. modulate the activity of other endocrine glands
51
Q

anterior pituitary

A

adenohypophysis; glandular portion of pituitary

highly vascularized
contains epithelial cells

52
Q

pars of the anterior pituitary

A

pars distalis
pars intermedia
pars tuberalis

53
Q

pars distalis

A

anterior lobe; main glandular part and site of majority of hormone production

cords of epithelial cells surrounding fenestrated capillaries that extend from the hypothalamus

contains secretory granules w/ hormones

54
Q

pars intermedia

A

intermediate lobe between the anterior and posterior pituitary

some hormone production

55
Q

pars tuberalis

A

non-secretory tissue that surrounds the infundibular stalk

provides support

56
Q

posterior pituitary

A

neurohypophysis; neural portion of the pituitary

contains axon terminals of hypothalamic neurons (neuroendocrine cells)

57
Q

pars nervosa

A

neural lobe

non-myelinated axons with neurosecretory activity (hormones produced in hypothalamus and transported to pituitary via secretory granules and stored in pituitary in herring bodies)

hormones: ADH, oxytocin

58
Q

infundibular stalk

A

pituitary stalk

59
Q

median eminence

A

extension of the base of the hypothalamus; down growth of neural tissue into a capillary bed

60
Q

what are the two main capillary beds in the pituitary

A
  1. primary plexus
  2. secondary plexus
61
Q

primary plexus

A

capillary bed where neural cells can release releasing hormones (small peptides)

drains into the large capillary bed of the adenohypophysis via portal veins

62
Q

secondary plexus

A

large capillary bed within the adenohypophysis where the releasing factors bind to receptors to stimulate release of hormones into systemic circulation

63
Q

thyroid gland

A

endocrine gland essential for normal growth and development

has large extracellular storage compartment within follicle lumen (stores hormone precursors)

highly vascularized

produces T3/T4 to increase metabolic rate

64
Q

thyroid follicles

A

single layer of cuboidal epithelial cells (follicular epithelium) surrounding a colloid-filled lumen

65
Q

what is the colloid made of

A

contains thyroglobulin and proteolytic/mucoproteins

66
Q

what does shape of follicular cells depend on

A

activity level
active = columnar
inactive - cuboidal

67
Q

principal/follicular cells

A

secrete thyroglobulin and create T3/T4

smaller, darker staining

68
Q

parafollicular cells

A

secrete calcitonin to regulate calcium

paler staining

69
Q

adrenal gland

A

endocrine gland located above the kidneys

secretes steroids and catecholamines

70
Q

adrenal cortex

A

secretes steroids (cortisol, aldosterone, androgen)

71
Q

blood supply of the adrenal gland

A

capsular plexus surrounds the adrenal, branches into the fenestrated cortical capillaries and medullary artery

72
Q

fenestrated cortical capillaries

A

drains from capsular plexus to supply blood throughout the layers of the cortex and into the medulla; drains into the central vein in the medulla

73
Q

what are the zones of the cortex

A
  1. zona glomerulosa
  2. zona fasciculata
  3. zona reticularis
74
Q

zona glomerulosa

A

outermost layer; produces mineralocorticoids (aldosterone)

contains sup capsular arterial plexus

columnar or pyramidal cells in rounded clusters

75
Q

zona fasciculata

A

middle layer; produces glucocorticoids (cortisol)

long cords of large/spongy cells separated by collagen and capillaries

contains lipid droplets (pale staining)

76
Q

zona reticularis

A

innermost layer; produces sex steroids (DHEA)

smaller, irregular cords/clusters that are closely arranges

less lipid droplets (darker)

77
Q

adrenal medulla

A

secretes catecholamines (epinephrine, norepinephrine)

78
Q

medullary artery

A

direct blood supply to the medulla; bypasses the cortical capillaries to allow for rapid release of catecholamines into circulation

79
Q

central vein

A

located within the medulla; drains the cortical capillaries and medullary artery

80
Q

dual blood supply of the medulla

A

medulla receives blood from the medullary artery (direct) and fenestrated cortical capillaries (shared with the cortex)

81
Q

chromaffin cells

A

modified postganglionic sympathetic neurons

have secretory granules containing epinephrine and norepinephrine

82
Q

how does signaling in the adrenal medulla work

A
  1. preganglionic fibers terminate on chromaffin cells and release Ach
  2. stimulates catecholamine synthesis and secretion
83
Q

endocrine pancreas

A

regions of endocrine cells within the otherwise exocrine tissue

function: regulate blood glucose levels

84
Q

islets of langerhans

A

regions of endocrine cells (a, b, d) within the pancreas

highly vascularized - arterioles enter islets directly and branch into capillaries

85
Q

what do the cells of the islets of langerhans produce

A

a cells: glucagon
B cells: insulin
d cells: somatostatin

VET 410: Endocrinology (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions