Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

..3 > Introduction To The Endocrine System > Flashcards

Introduction To The Endocrine System Flashcards

1
Q

What is the purpose of the endocrine system?

A

◦ Regulation of multiple organs to meet growth and reproduction demands

◦ Major role in homeostasis

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

What are the classical endocrine glands?

A 
Hypothalamus
Anterior/posterior pituitary
Thyroid
Parathyroid
Adrenal cortex/medulla
Gonads
Pancreas
Placenta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What major hormones does the hypothalamus produce?

A
  • ADH (PVN)
    * Oxytocin (SO)
    * TRH
    * GRH
    * GHRH
    * GnRH
    * Somatostatin
    * Dopamine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What major hormones does the anterior pituitary produce?

A
  • ACTH
    * TSH
    * Growth hormone
    * Prolactin
    * FSH
    * LH
    * MSH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What major hormones does the posterior pituitary produce?

A
  • Oxytocin

* ADH

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

What major hormones does the thyroid produce?

A
  • Thyroxine (T4)
    * Triiodothyronine (T3)
    * Calcitonin (CT)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What major hormones does the Parathyroid produce?

A

• Parathyroid hormone (PTH)

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

What major hormones does the adrenal cortex produce?

A
  • Cortisol
    * Aldosterone
    * Androgens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What major hormones does the adrenal medulla produce?

A
  • Epi

* Norepinephrine

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

What major hormones do the Testes produce?

A
  • Androgens (esp. testosterone)

* Inhibin

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

What major hormones do the Ovaries produce?

A
  • Estrogens (estradiol)
    * Progesterone
    * Inhibin
    * Relaxin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What major hormones do the Pancreatic Islets produce?

A
  • Insulin
    * Glucagon
    * Somatostatin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What major hormones does the Placenta produce?

A
  • HCG
    * hPL
    * Estriol
    * Progesterone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What major hormones does the corpus luteum produce?

A
  • Estradiol

* Progesterone

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

Where are there endocrine cells in a non-endocrine organ?

A 
Adipose 
Kidneys
Liver
Heart
GI tract
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What major hormones do the Kidneys release?

A

◦ Renin

◦ 1,25 Dihydroxycholecalciferol

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

What can also modify hormones?

Examples?

A

Peripheral conversion

Angiotensin II

Vit. D from sun

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

What constitutes a proteins?

A

Polypeptide with >100 AAs

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

What constitutes a peptide?

A

Polypeptide with < or equal to 100 AAs

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

Are protein/peptide hormones lipid or water soluble?

A

Water soluble

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

How are protein/peptide hormones synthesized?

A

‣ Synthesized as Non-functional pre-prohormone

‣ Modified in ER —> pro-hormone —> Golgi apparatus s

‣ Packed into vesicles

‣ Cleaved by proteolytic enzymes to form functional hormone

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

What are protein/peptide hormones stored in?

When are they secreted?
Example?

A

In secretory vesicles

Secreted w/ endocrine stimulus

(Increased intracellular Ca —> increase cAMP —> PKA activation)

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

What are examples of steroid hormones?

A 
‣ Cortisol
		‣ Aldosterone
		‣ Estradiol
		‣ Estriol
		‣ Progesterone
		‣ Testosterone
		‣ 1,25-dihydroxycholecalciferol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Are steroid hormones lipid or water soluble?

A

Lipid soluble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How are steroid hormones synthesized?
‣ From cholesterol ‣ modifications of cholesterol via addition or removal of side chains, hydroxylation or aromatization of the steroid nucleus
26
Where are steroid hormones synthesized at?
• Adrenal cortex, gonads, corpus luteum, placenta
27
How are steroid hormones stored? Secreted?
They are not stored Secreted by adrenal cortex, gonads, corpus luteum, placenta
28
What are the 2 groups of amine hormones?
Catelcholamines Thyroid hormones
29
How are catelcholamine hormones synthesized? Secreted?
‣ Derived from Tyrosine ‣ Synthesized in cytosolic and secretory granules ‣ Secretion: Act thru cell membrane assoc. receptors
30
How are thyroid hormones synthesized? Secreted?
‣ Synthesized by Thryoid gland ‣ Stored as thyroglobulin in follicles w/in the gland ‣ Secretion: Cross cell membrane & act thru nuclear receptors
31
What two mechanisms control hormone secretion?
Neural and feedback
32
What is the neural mechanism that controls hormone secretion?
‣ Neuronal input to endocrine cell increases or decrease hormonal secretion
33
What is an example of neural mechanism of controlling hormone secretion?
sympathetic preganglionic innervation to adrenal medulla = causes release of Catecholamines into circulation
34
What mechanism is more common in controlling hormone secretion, neural or feedback
Feedback
35
How does the feedback mechanism for controlling hormonal secretion work?
element of pathway feeds back, directly or indirectly, on endocrine gland to change secretion rate
36
What is a positve endocrine feedback ?
◦ Hormone action causes additional secretion of hormone | ◦ Uncommon in biological system
37
What can a positive endocrine feedback lead to? Example?
‣ Can lead to explosive event • Ovulation or labor contractions
38
What is a Negative Endocrine Feedback? Purpose?
◦ Hormone action inhbits further secretion of the hormone ◦ Confers stability by keeping a physiological parameter (i.e. blood glucose level) w/in a normal range
39
What is the pathway for a LONG feedback loop?
‣ Hormone released from peripheral endocrine gland (3rd tier) —-goes back to —-> 1st tier (hypothalamus) and 2nd tier (pituitary)
40
What is the pathway for a SHORT feedback loop?
Hormone from 2nd tier (pituitary) —> 1st tier (hypothalamus)
41
What is the ULTRA SHORT feedback loop?
Gland inhibits its own secretions
42
How is the hypothalamus regulated?
By descending and ascending neuronal inputs From Suprachiasmatic nucleus, pineal glands, physiological stress
43
What is the “first tier” of the endocrine axes?
Hypothalmus
44
What does the suprachiasmatic nucleus Regulate? How?
Hypothalamus Thru imposing circadian rhythm on secretion of hypothalamic releasing hormone and endocrine axes
45
What does the pineal gland regulate? How?
Hypothalamus Releases melatonin to feed back to SCN re: info about day and night
46
What does physiological stress regulate? How?
Hypothalamus Influences the release of hormones from hypothalamus
47
How is sensitivity defined?
[hormone] that produces 50% of maximal response (EC50)
48
What is the dose-response relationship regulate?
Responsiveness of target tissue
49
How can you change the responsiveness of tissues to hormones?
Change # of receptors Change affinity of receptors for hormones
50
What are the mechanisms for up-regulation ? When would you upregulate?
◦ Increase # of receptors OR sensitivity of target tissue when hormone level is low
51
What are the mechanisms for down-regulation ? When would you downregulate?
◦ Reduce # of receptors OR sensitivity of target tissue when hormone levels are high (Chronic)
52
How would you enact up-regulation?
‣ Increasing synthesis of new receptors ‣ Decreasing degradation of old ‣ Activating receptors
53
How do you enact down-regulation ?
‣ Decreasing receptor synthesis ‣ Increasing degradation of receptors ‣ Inactivating/desensitizing receptors
54
What are the hormones that act thru adenylyl cyclase pathway? What is the mechanism?
ACTH, LH, FSH, TSH, Glucagon 1st messenger hormone —> receptor Gs activated —> primary effector-adenylyl cyclase 2nd messenger cAMP —> 5AMP —> PKA active now = secondary effector PKA —> phosphorylate proteins —> physiological actions
55
What hormones will act thru Phospholipase C pathway?
GnRH, TRH, Oxytocin
56
What is the mechanism of hormone action using the Phospholipase C pathway?
1st messenger hormones —> receptor Gq activated —> Phospholipase C (primary effector) Phospholipase C —> IP3, DAG, Ca (2nd messenger) —> PKC or Calmodulin (secondary effector)
57
How do steroid hormones diffuse into target cell?
Diffuse UNbound to plasma protein carriers
58
What is the signal transduction pathway for steroid hormones?
Steroid diffuses into target cell Bind steroid hormone r. On cytoplasm or NUCLEUS If nucl —> binds DNA, activating/repressing 1 or more genes Activated genes —> new mRNA —> mRNA back to cytoplasm —> Translation at ER —> new proteins made for cell processes
59
What do steroid hormones that bind to membrane receptors do?
Use second messenger system to create RAPID response
60
What is Guanylyl Cyclase do when activate?
Convert GTP to cGMP CGMP —> activates cGMP kinase Relax vascular smooth muscle
61
What are the 2 categories for tyrosine kinases?
1. Receptor tyrosine kinases | 2. Tyrosine kinase associated receptors (jak-stat)
62
What are the characteristics of Receptor Tyrosine Kinases? When active, what will they do?
Have intrinsic tyrosine kinase activity Will phosphorylates downstream proteins
63
What are the characteristics of Tyrosine Kinase Associated Receptors? What will they do when active?
associate non-covalently to proteins that have kinase activity Active kinase phosphylates downstream proteins
64
What is the relationship to the amount of hormone bound to protein and its half life and clearance?
Increase protein binding by hormone Will INCREASE 1/2 half DECREASE metabolic rate (clearance)
64
What are the three tiers of the endocrine system?
Tier 1: hypothalamus Tier 2: pituitary Tier 3: target of pituitary
64
What are the three general classes of hormones?
Proteins and peptides Amines Steroids
64
What are endocrine cells?
Release hormone thru blood which can act on a DISTANT cell that will then produce an effect
64
What is a paracrine cell?
Acts on NEARBY cell using hormone and then that cell will have effect
64
What is an Autocrine cell?
Acts on the SIGNALING cell using hormone released by itself
64
What are neuroendocrine cells?
Cells that receive neuronal input (NTRs released by nerve cells or neruocsecretroy cells) and release hormone into blood to act on distant cell

..3 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions