Introduction to the Physiology and Pharmacology of the Endocrine System Flashcards Preview

The Endocrine System > Introduction to the Physiology and Pharmacology of the Endocrine System > Flashcards

Flashcards in Introduction to the Physiology and Pharmacology of the Endocrine System Deck (60)
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1

The endocrine system essentially consists of many ___________ glands

The endocrine system essentially consists of many ductless glands

2

How is the specificity of signalling achieved in the endocrine system?

  1. Chemically distinct hormones
  2. Specific receptors
  3. Distinct distribution of receptors across target cells

3

Why is specificity of signalling required in the endocrine system?

Hormones in the blood stream can reach any tissue

(and only "need" to act on certain tissues)

4

What are the 4 main secretion types from endocrine glands?

  1. Modified amino acids
  2. Steroids
  3. Peptides
  4. Proteins

5

Give an example of a modified amino acid secretion from an endocrine gland?

  1. Adrenaline
  2. Thyroxine (T4)
  3. Triiodothyronine (T3)

6

Give an example of a steroid hormone

  1. Cortisol
  2. Progesterone
  3. Testosterone

7

What do all steroid hormones originate from?

Cholesterol

8

Give an example of a peptide hormone

  1. Adrenocorticotropic hormone (ACTH)
  2. Anti-diuretic hormone (ADH)
  3. Oxytocin

9

Peptide hormines come from _________ ___________ proteins

Peptide hormines come from larger precursor proteins

10

Give an example of a protein hormone

Insulin

11

What are the 7 main endocrine organs?

  1. Pituitary gland
  2. Thyroid gland
  3. Parathyroid glands
  4. Adrenal glands
  5. Pancreas
  6. Ovary
  7. Testis

12

What is autocrine signalling?

When a cell is both the originator and recipient of the signal

13

What is paracrine signalling?

Signalling molecules travel short distances by diffusion and act on cells close by

(they do not enter systemic circulation)

14

What is endocrine signalling?

Hormone is released into the circulation and reaches the target organ this way

15

Hormones can only function in one of the following three ways, autocrine, paracrine or endocrine. True or false?

False

(hormones can function in more than 1 way)

16

Why do receptors for endocrine hormones have very high affinity for hormone?

Organ function is regulated at very low hormone concentrations

17

Endocrine hormones have high ________

Endocrine hormones have high potency

18

Due to the scarcity of the endocrine hormone signal, what does the target cell do to combat this?

Signal transduction pathways amplify the original signal

19

The onset and duration of hormone action is fairly consistent.

True or false?

False

It is highly variable froms seconds to days

20

The onset and duration of hormone action depends on deactivation of enzyme, but which two locations does this mainly occur at?

  1. Enzyme mediated deactivation in the liver
  2. Deactivation at the site of action

21

Which two categories of functions can hormones have?

  1. Complementary
  2. Antagonistic

22

Are amines either presynthesised or synthesised and secreted on demand?

Presynthesised

23

When would amines be released?

In response to stimuli by Ca2+ dependent exocytosis

24

What are the three key characteristics of amines?

  1. Small
  2. Water soluble
  3. Released on demand

25

Are peptides and proteins either presynthesised or synthesised and secreted on demand?

Presynthesised

26

When would peptides and proteins be released?

In response to Ca2+ dependent mechanisms

27

In terms of peptides and protein hormones, what is the general term given to enzymes which alter the precursor to the mature hormone?

Convertases

28

Cholesterol is converted to steroid hormones via which intermediate?

Pregnenolone

29

Are steroids either presynthesised or synthesised and secreted on demand?

Synthesised and secreted on demand

30

How do steroid hormones travel in the plasma and why?

Via steroid binding proteins

They are very sparingly soluble in water (mostly hydrophobic)