1s- Hydrophilic signalling molecules and transduction Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What do hydrophilic signalling molecules bind to?

A

They bind to transmembrane receptors and do not enter the cytosol

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

What are two examples of hydrophilic extracellular signalling molecules?

A
  • peptide hormones

- neurotransmitters

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

What do transmembrane receptors do when the ligand binds to the extracellular face and what happens to the signal molecule that is produced?

A

The transmembrane receptor changes conformation and the signal molecule does not enter the cell but the signal is transduced across the plasma membrane

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

How do transmembrane receptors act as signal transducers?

A

By converting the extracellular ligand-binding event into intracellular signals, which alters the behavior of the cell

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

What do transduced hydrophilic signals often involve?

A

G-proteins or cascades of phosphorylation by kinase enzymes

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

What do G-proteins do?

A

Relay signals from activated receptors (receptors that have bound a signalling molecule) to target proteins such as enzymes and ion channels

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

What do phosphorylation cascades allow to?

A

More than one intracellular signalling pathway to be activated

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

What do phosphorylation cascades involve?

A

A series of events with one kinase activating the next in the sequence and so on

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

What can phosphorylation cascades result in?

A

The phosphorylation of many proteins as a result of the original signalling event

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

What does the binding of the peptide hormone insulin to its receptor result in?

A

An intracellular signalling cascade that triggers recruitment of GLUT4 glucose transporter proteins to the cell membrane of fat and muscle cells

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

What does the binding of insulin to its receptor cause to happen?

A

A conformation change that triggers phosphorylation of the receptor. This starts a phosphorylation cascade inside the cell , which eventually leads to GLUT4-containing vescicles being transported to the cell membrane

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

There are two types of diabetes mellitus; type 1 and type 2. What are they both caused by?

A

Type 1 = failure to produce insulin

Type 2 = loss of receptor function

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

What is type 2 diabetes generally associated with?

A

Obesity

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

Why is exercise beneficial for people with type 2 diabetes?

A

It triggers recruitment of GLUT4, which improves uptake of glucose to fat and muscle cells in those with type 2 diabetes

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