Cell signalling Flashcards

1
Q

What processes does the endocrine system influence?

A

Metabolism, growth and reproduction

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

What mediators does the endocrine system release?

A

Hormones

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

What is a Hormone?

A

Chemical messenger released by endocrine glands to regulate activity of cells in other parts of body

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

What do circulating hormones do?

A

Secreted by endocrine cells into bloodstream, travel through bloodstream to target cells
Exert effect via receptors expressed on target cells

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

What organ inactivates circulating hormones?

A

Liver

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

What organ excretes circulating hormones?

A

Kidneys

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

What do local hormones do?

A

Secreted by one cell type into extracellular fluid to affect surrounding cells
Exert effect via receptors expressed on surrounding cells

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

Examples of local hormones

A

Paracrine hormones e.g. Histamine
Autocrine hormones- e.g. Interleukin 2 (IL-2)
local hormones that act of the same cell that secreted them

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

What are the two types of ways hormone can be transported around the body?

A

Water soluble hormones

Lipid soluble hormones

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

What are water soluble hormones?

A

Hormones that circulate freely within the blood

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

What are lipid soluble hormones?

A

Hormones that are bound to proteins, which are temporarily water soluble

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

Are hormones specific or non-specific?

A

Specific- can only affect specific target cells

Only target cells for a specific hormone will express receptors for that hormone

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

Where are hormone receptors located?

A

Within the target cell or on the target cell membrane

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

What happens after the lipid soluble hormones bind to receptors within target cells?

A

Activated-receptor hormone complex alters gene expression

mRNA directs synthesis of a new protein (enzyme) which alters cell’s activity

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

Where do water soluble hormones bind?

A

Receptors on cell membrane

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

What happens when the water soluble hormones bind to the receptors?

A

Hormone-receptor complex activates a G-protein

17
Q

What happens after the G-protein is activated by the water soluble hormone?

A

Activates a cascade of events which amplify the reaction

Cellular proteins are activated or inhibited, and a physiological response is produced

18
Q

What feedback loop does the endocrine system take?

A

Negative feedback loop

19
Q

What is the nervous system?

A

A regulatory system composed brain, spinal cord and nerves

20
Q

What does the Central Nervous System control?

A

Controls movement, intellectual and physiological function, detects and processes sensory information

21
Q

What mediators do the Nervous System release?

A

Neurotransmitters

22
Q

What is a neurotransmitter?

A

Chemical messengers released by neurones to regulate activity of other neurones, glands and muscles

23
Q

What releases neurotransmitters?

A

Neurone releases it into a synapse

24
Q

What is a synapse?

A

Region where communication occurs between a neurone and an effector cell (muscle or gland) or another neurone

25
Q

What happens after a Neurotransmitters (NTs) released into chemical synapse?

A

NTs diffuse through synaptic cleft and bind to specific receptors on target cell
NT binding to receptor activates one of many pathways
Like hormones , can activate a G-protein cascade which produces a physiological response

26
Q

How do electrical synapses release neurotransmitters?

A

Ions flow directly between adjacent cells through a gap

Gap junction connects cytosol of two cells together

27
Q

Where are gap junctions found?

A

Smooth muscle, cardiac muscle and developing embryo

28
Q

What neuropeptides are released from nerves in hypothalamus?

A

Oxytocin

Vasopressin

29
Q

What do the endocrine and nervous system have in common?

A

Both associated with the brain
Same molecules can be both neurotransmitters and hormones
Two systems work simultaneously to regulate critical body processes

30
Q

What are the differences between the nervous and endocrine systems?

A

Endocrine secretes hormones that are transported in the bloodstream
Nervous system secretes neurotransmitters released directly onto target cells
Nervous system- activates targets quickly not long lasting
Endocrine system- longer lasting effects

31
Q

What are hormones physiological functions?

A
Temperature control
Thirst
Hunger
Mood 
Sex drive
32
Q

What is paracrine signalling?

A

Cell-cell signalling

33
Q

What is synaptic signalling?

A

Between cells with a synapse in between

34
Q

What is autocrine signalling?

A

Cell secretes hormone/messenger

35
Q

What is contact-dependent cell signalling?

A

Close contact signalling