Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biomedical Physiology > Cell Signalling > Flashcards

Cell Signalling Flashcards

1
Q

Cell to cell communication can be of two types, what are these?

A

Direct and indirect cell communication

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

What are the four principle types of cell signalling in animals?

A

Direct - gap junctions
Autocrine and paracrine signalling
Endocrine signalling
Neural signalling

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

Describe how direct signalling may take place.

A

Adjacent cells may communicate directly through aqueous pores - GAP JUNCTIONS

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

Describe the process of indirect cell signalling in four stages

A
  1. Cell releases chemical messenger to extracellular env
  2. Chemical messenger transported to target cell
  3. Communication of signal to target cell via receptor binding
  4. Signal transduction pathways activated that cause a response within the cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

On what scale does the indirect cell signalling of paracrines work?

A

On a local scale

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

In paracrine cell signalling, how do the chemical messengers travel from the signalling cell to the target cell?

A

By diffusion

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

On what scale does the indirect cell signalling method of autocrines work?

A

Local scale

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

What is the difference between autocrine and paracrine cell signalling?

A

With autocrine signalling, the chemical messenger causes a response in the signalling cell whereas with paracrine signalling, the chemical messengers target a nearby cell

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

On what scale does endocrine cell signalling work?

A

Long distance

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

How does the chemical messenger travel in endocrine signalling?

A

In the circulatory system

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

What are endocrine messengers?

A

They are hormones

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

In neural signalling which is a type of indirect cell signalling, how is the signal transferred to the target cell in terms of distance?

A

Short distance

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

In neural singalling, the electrical signals travel over ____ distances within a single cell.

A

Long

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

Chemicals can be either h____ or h____

A

Hydrophobic or hydrophilic

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

Hydrophobic chemical messengers are soluble in

A

Lipids

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

Hydrophobic chemical messengers can/can’t pass through cell membranes

A

CAN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Hydrophobic messengers do/do not dissolve in aqueous fluids such as the cytoplasm or the blood

A

DO NOT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Hydrophilic chemical messengers are soluble in

A

Aqueous solutions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Can hydrophilic chemical messengers pass through cell membranes?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Are hydrophilic chemical messengers soluble in the cytoplasm and ECF?

A

YAS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

There are six main classes of chemicals involved in cell signalling, what are these?

A

Peptides, steroids, amines, lipids, purines and gases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Peptides, steroids and amines are all known

A

hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The six main classes of chemicals involved in cell singnalling can be involved in

A

autocrine, paracrine and neurotransmitter cell to cell singalling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Peptide messengers can exist as what three types?

A

Amino acids, peptides and proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are amino acids normally involved in cell signalling as?
Neurotransmitters
26
What are peptides normally involved in cell singalling as?
Autocrines, paracrines, neurotransmitters, neurohormones, hormones and pheromones
27
What are proteins normally involved in cell signalling as?
Autocrines, paracrines, neurotransmitters, neurohormones, hormones and pheromones
28
What is the difference between peptides and proteins in terms of amino acids?
Peptides 50 AA
29
What is a neurohormone?
A substance produced by nerve cells (neurosecretory neurones) and secreted into the circulation
30
Give two examples of neurohormones
Vasopressin and adrenaline
31
Are peptide messengers hydrophobic or hydrophilic?
Hydrophilic
32
Where are peptide messengers synthesisied?
In the rough ER
33
Peptide messengers are packaged into
vesicles
34
Peptide messengers can be used immediately or
stored
35
What type of peptide messengers are stored?
Peptide hormones and neurotransmitters
36
What type of peptide messengers are made on demand?
Paracrine peptides such as cytokines
37
How are peptide messengers released from the cell?
By exocytosis
38
What is exocytosis?
When a secretory vesicle fuses with the plasma membrane releasing the vesicle contents to the cell exterior
39
How are peptide messengers transported?
Easily through aqueous solutions
40
What happens to peptide messengers in the extra cellular fluid?
They are broken down in the ECF by proteolytic enzymes
41
What is the half life of peptide messengers?
The rate of breakdown of the peptide messengers by the proteolytic enzymes present in the ECF
42
Is the half life of peptide messengers short or long?
Short - few seconds - few hours
43
Why must peptide messengers be produced at a constant rate for a sustained response?
Because they have a short half life so won't have a lasting effect
44
What is the issue with peptide messengers reaching their target cell?
Peptide messengers are hydrophilic so cannot cross the plasma membrane easily
45
How do peptide messengers cause a response in their target cell as they cannot cross the plasma membrane easily.
They bind to transmembrane receptors, conformational change of receptor, activated singal transduction pathways
46
What are steroid messengers derived from?
cholestrol
47
Steroid messengers can be which types of messenger?
Hormones in vertebrates and invertebrates, paracrine/autocrine in some tissues and pheromones in animal-animal communication
48
There are three classes of steroid messengers in vertebrates, what are these?
Mineralocorticoids, glucocorticoids and reproductive hormones
49
Give an example of a steroid messenger from the class mineralocorticoids.
Aldosterone - sodium reabsorption
50
Give an example of a steroid messenger from the class glucocorticoids
Cortisol - manage stress & metabolism
51
Give two examples of steroid messengers from the class of reproductive hormones
Eostrogens and testosterone
52
How are steroid hormones synthesised?
Enzymes for steroid biosynthesis located in smooth er or mitochondria
53
How are steroid hormones secreted?
Directly through the membrane because they are hydrophobic -
54
Can steroid hormones be stored?
No because they are hydrophobic
55
At which distance can steroid messengers be transported?
Short and long distance
56
How are steroid messengers transported short distances?
By diffusion - dissolved in the extracellular fluid
57
How are steroid messengers transported long distances?
By being bound to carrier proteins
58
Steroid messengers can travel long distances by specific or non specific carrier proteins, give an example of a specific and an example of a non specific carrier protein.
Specific - globulins and non specific - albumin
59
Steroid messengers are transported either bound to a carrier protein or as...
free messengers
60
What percentage of steroid messengers are transported bound to a carrier protein and what percentage of steroid messengers are transported as free messengers?
Over 99% are bound to a carrier protein and below 1% are transported as free messengers
61
What is the equation of law of mass action and equilibrium and what does each letter stand for?
M + C ->-
62
What happens in the law of mass action and equilibrium in terms of steroid messengers?
Local conc of messenger is high near signalling cell Most of messenger binds to carrier proteins circulatory sys carries free and bound to target cell Free messengers enter target cell decresed conc of free messenger causes bound messenger to dissociate from protein and also enter cell
63
How do steroid messengers interact with the target cell?
By binding to the receptors to exert an effect
64
What are the two types of receptors steroid messengers may bind to?
Transmembrane and intracellular receptors
65
What is an intracellular receptor?
Intracellular receptors are receptors located inside the cell rather than on its cell membrane.
66
What is a transmembrane receptor?
This type of receptor spans the plasma membrane
67
When a steroid messenger binds to intracellular receptors what happens?
Act as transcription factors > control expression of target genes • Pathway involves transcription & translation > time lag
68
When a steroid messenger binds to a transmembrane receptor, what happens?
Binding activates signal transduction pathway | • Causes rapid non-genomic effect
69
What are biogenic amines?
A chemical messenger obviously but chemicals containing an amine group attached to carbon atom
70
What is an amine group?
``` Amine group (-NH2 ) ```
71
Are biogenic amines hydrophobic or hydrophilic?
Most are hydrophilic
72
What can the synthesis and release of biogenic amines be compared to as they have the same properties in terms of hydrophobicity?
synthesis & release similar to peptides
73
What are many biogenic amines synthesised from?
Many synthesised from AAs
74
The biogenic amine catecholamines are synthesised from which amino acid?
Tyrosine
75
The biogenic amine thyroid hormone is synthesised from which amino acid?
Tyrosine derivative
76
The biogenic amine serotonin and melatonin are synthesised from which amino acid?
Tryptophan
77
The biogenic amine histamine is synthesised from which amino acid?
Histadine
78
The biogenic amine acetylcholine is synthesised from which amino acid?
Choline & acetyl-coenzyme A
79
What may the biogenic amine catecholamines act as?
neurotransmitters, paracrines, hormones
80
Give three examples of catecholamines and what do they act as?
Dopamine - neurotransmitter Noradrenalin & adrenalin – neurotransmitters, paracrines, hormones
81
The biogenic amine thyroid hormones act as?
hormones
82
The biogenic amine serotonin acts as?
Seratonin - neurotransmitter
83
The biogenic amine melatonin acts as?
Melatonin – neurotransmitter & hormone
84
The biogenic amine histamine acts as?
Histamine – neurotransmitter & paracrine
85
The biogenic amine acetylcholine acts as?
Acetylcholine – primary neurotransmitter at NMJ

Biomedical Physiology (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions