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Flashcards in Physiology Deck (45)
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1

The endocrine system involves ducts. True/False?

False
It is a ductless system involving glands that secrete directly into blood

2

How is specificity of signalling by endocrine glands achieved?

Chemically distinct hormones
Specific hormone receptors
Distinct distribution of receptors

3

List the main endocrine glands of the body

Hypothalamus
Pituitary
Parathyroid
Thyroid
Adrenal gland
Pancreas
Placenta
Ovaries/testes

4

What is meant by an autocrine gland?

Hormone released acts back on the structure that released it

5

What is meant by a paracrine gland?

Hormone released acts on neighbouring structures

6

List the 3 main classes of hormones

Glycoproteins + peptides
Steroids
Tyrosine derivatives

7

Give an example of glycoprotein/peptide hormones

Insulin
Growth hormone
Oxytocin
Prolactin

8

Give an example of a steroid hormone

Cortisol
Testosterone

9

Give an example of a tyrosine-derivative hormone

Adrenaline
Thyroid hormone
Melatonin

10

A whole protein is always required to achieve hormonal effect. True/False?

False
Protein can be cleaved into active hormonal units

11

On a basic level, how are amines, peptides and proteins released from the endocrine cell?

Synthesised, packaged into vesicles and then released in response to stimuli via exocytosis

12

On a basic level, how are steroid hormones released from the endocrine cell?

Synthesised upon demand, then stimuli increases cellular uptake and availability of cholesterol + rate of conversion into pregnenolone, which is then used to build steroid to be released

13

Steroid hormones travel freely in blood. True/False?

False
Usually has carrier protein in inactive form

14

Which carrier protein binds cortisol?

Cortisol-binding protein! FANCY THAT

15

Which carrier protein binds thyroxine (T4)?

Thyroxine-binding globulin

16

Which hormones normally bind to sex steroid-binding globulin?

Testosterone
Estradiol

17

Free and bound lipophilic hormone are in equilibrium in the blood. True/False?

True

18

What does "tropic" mean with regards to hormones?

Refers to a hormone that acts upon another endocrine gland to regulation secretion of hormone

19

What are the biggest players in elimination of hormone?

Liver
Kidney

20

Time taken to reach half life of amine hormones is achieved in seconds/minutes/hours

Seconds

21

Time taken to reach half life of protein hormones is achieved in seconds/minutes/hours

Minutes

22

Time taken to reach half life of steroid hormones is achieved in seconds/minutes/hours

Hours

23

List the 3 main distinct types of hormone receptor

GPCR
Receptor kinases
Nuclear receptors

24

Which of the 3 main types of hormone receptor are cell surface receptors?

GPCR
Receptor kinases

25

Which of the 3 main types of hormone receptor are intracellular receptors?

Nuclear kinases

26

Describe class 1 nuclear receptors

Activate by steroid hormones
Usually in cytoplasm bound to heat-shock-proteins

27

Describe class 2 nuclear receptors

Activate by lipids
Present in nucleus

28

Describe the hybrid class of nuclear receptors

Activated by T3
Similar function to class 1

29

Give an example of a hormone that utilises signalling via receptor kinases

Insulin

30

What are the 3 main components of the hypothalamic pituitary axis?

HYPOTHALAMUS influences PITUITARY to secrete hormones to act on PERIPHERAL GLAND (thyroid, adrenal etc.)