Endocrinology Flashcards Preview

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Flashcards in Endocrinology Deck (21)
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1
Q

Define hormone

A

A chemical messenger which travels via the bloodstream

2
Q

What are the 4 chemical types of hormones?

A

Polypeptide hormones
Glycoprotein hormones
Amino acid derivatives
Steroids (derived from cholesterol)

3
Q

How are hormones transported?

A

Hydrophillic ones are dissolved in the plasma

Hydrophobic ones eg steroid/thyroid hormones have carrier proteins

4
Q

How does the effect of hormones vary with changing plasma concentrations?

A

It is the concentration of free hormone that has effects.
If the concentration is low, the person is said to have a deficiency.
If the concentration is high, the person will have symptoms of excess

5
Q

Which type of hormone can bind to receptors inside a cell?

A

Lipophilic hormones

6
Q

Which type of hormone can bind to receptors on the surface of a cell?

A

Hydrophilic hormones

7
Q

What can cause a rapid response to hormones in target tissues?

A

Hormones that act on the activity of functional proteins

8
Q

What can cause a long term response to hormones in target tissues?

A

Hormones that change gene expression

9
Q

How can hormone secretion be controlled?

A

Negative feedback
One hormone controlling another
Releasing/Inhibiting hormones
Inactivation of hormones

10
Q

How does negative feedback work?

A

Blood concentration levels of the hormone controls how much hormone is secreted

11
Q

What is a hormone which controls release of another hormone called?

A

A trophic hormone

12
Q

Where are most inhibitory/stimulatory hormones released from?

A

Nerve cells in the hypothalamus

13
Q

Where can inactivation of enzymes occur?

A

Liver
Kidney
Target tissue

14
Q

How are steroid hormones inactivated?

A

Small change in structure so they become soluble. Then excreted in bile or urine.

15
Q

How are protein hormones inactivated?

A

Extensively broken down then the amino acids are reused.

16
Q

Where is insulin stored?

A

In beta cell storage granules

17
Q

Which is anabolic out of Insulin and Glucagon?

A

Anabolic - Insulin

Catabolic - Glucagon

18
Q

What are the long and short term effects of insulin?

A

Long - cell growth/division

Short - clearing absorbed nutrients from the blood after a meal

19
Q

What are the major actions of Glucagon?

A
Glycogenolysis
Glycogenesis (decreased)
Gluconeogenesis
Ketogenesis
Lipolysis
20
Q

What are the major actions of Insulin?

A

Opposite to Glucagon

Increased glucose transport into adipose tissue/skeletal muscle

21
Q

What are the 2 sections to an Islet of Langerhans cell?

A

Beta cells - produce insulin

Alpha cells - produce Glucagon