Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HUMAN BIO > 2.4 > Flashcards

2.4 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

3 basic parts of neurons

A

Dendrites
Cell body
Axons

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

Dendrites

A

Nerve fibres that can receive nervous signals from another neuron or sense organ. They then pass these signals to the cell body

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

Cell body

A

Cell body contains cytoplasm, nucleus, mitochondria and ribosomes for the neuron. The DNA is important as it contains genes for production neurotransmitters

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

Axon

A

Long cell structure that can carry nervous signals at speed. The ends of the axon terminate at the synapse between 2 neurons. Axon surrounded by myelin sheath

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

What is axon surrounded by

A

Myelin sheath

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

Myelin sheath purpose

A

Insulates axon and allows speed of impulses to be increased , allowing cells to transmit signals more quickly. This is why children have slower reaction speeds

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

When is myelin sheath formed

A

Myelin sheath formed during early development (conception) (myelination)

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

Problems with myelin sheath if damaged

A

People lose coordination and speed in their movement. Neurones experience problems with correct transmission of signals

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

Disease of myelin example

A

Multiple Sclerosis (MS)

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

Synapse

A

The gap between two neurones.

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

How do electrical signals cross synapses

A

First neuron releases chemicals called neurotransmitters to cross the gap and activate a signal in the second neurone.

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

Synaptic cleft

A

Tiny region between the axon ending of one neurone and the dendrite of another neurone.

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

Presynaptic neuron

A

Neuron carrying signal before the synapse

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

Postsynaptic neuron

A

Neuron that generates signal after synapse

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

Neurotransmitter

A

Protein that crosses the synapse and binds to receptor on postsynaptic membrane

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

Vesicles

A

Small membrane bound organelles which act as containers for neurotransmitters.

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

What do vesicles do when electrical signal arrives

A

Rise to the surface of presynaptic membrane and fuse with the membrane to allow the release of neurotransmitters into synaptic cleft

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

Two ways you can dispose of neurotransmitters are

A

Reuptake by presynaptic membrane
Enzyme degradation (breakdown)

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

How does reuptake work

A

Presynaptic membrane contains receptors that can collect and re absorb the neurotransmitter back into the Presynaptic knob.

The neurotransmitter can then be repackaged into vesicles or broken down

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

Example of neurotransmitter reuptake

A

Adrenaline

21
Q

How does breakdown / enzyme degradation work

A

Certain enzymes act to break down specific neurotransmitters in the synaptic cleft, preventing them from further transmission

22
Q

Neurotransmitter enzyme degradation example

A

Acetylcholine

23
Q

Excitatory receptors

A

When a neurotransmitter binds to an excitatory receptor, the change of an impulse being created is increased

24
Q

Inhibitory receptors

A

If a neurotransmitter binds to an inhibitory receptor on the postsynaptic membrane, it decreases the chances of an impulse being created

25
Q

Threshold

A

In order for impulse transmission to be successful, there must be enough neurotransmitters bound to receptors on the postsynaptic membrane. This helps prevent constant stimulation of nervous pathways.

26
Q

Summation

A

If enough weak stimuli release enough neurotransmitters across a synapse, this can be enough to generate a signal in the postsynaptic neuron. (Several weak signals combining to reach threshold)

27
Q

Endorphins

A

Neurotransmitter released by brain. Stimulate neurones to reduce pain. Painkilling properties have been linked to improve mood and reduce depression.

28
Q

How to increase endorphins

A

Pain, intense exercise, stress, eating chocolate

29
Q

Dopamine

A

Neurotransmitter induces feelings of pressure and happiness . Involved in reward pathway

30
Q

Reward pathway

A

When body engages in beneficial behaviour, brain releases dopamine. Dopamine activates neurons which emit positive feelings, making them more likely to do it again.

31
Q

Behaviours that activate reward pathway

A

Eating when hungry
Drinking when thirsty
Having sex
Positive social interactions

32
Q

Types of neurotransmitter treatments

A

Agonists
Antagonists
Drugs that inhibit reuptake
Drugs that inhibit breakdown enzymes

33
Q

Agonists

A

Mimic the shape of a neurotransmitter. They can bind to receptors on the postsynaptic membrane and cause a similar action to the main neurotransmitter. They cause activation of those receptors in a similar way to the original neurotransmitter.

34
Q

Example of agonists used

A

Parkinsons treated by giving dopamine agonists.

35
Q

Antagonists

A

Antagonists bind to a receptor, but cause no action, blocking any neurotransmitters from stimulating the receptor. The normal action of the neurotransmitter, wether excitatory or inhibitory, is blocked.

36
Q

Antagonists example

A

Beta blockers, block noradrenaline

37
Q

Reuptake inhibitors

A

Allow the effects of some neurotransmitters to last longer as they prevent their reabsorptiom into the Presynaptic knob.

38
Q

Reuptake inhibitors example

A

Depression by seratonin Reuptake inhibitors (SSRIS)

39
Q

Neurotransmitter breakdown enzymes inhibitor

A

Prevent breakdown of neurotransmitters in the synaptic cleft, allowing for longer duration and more signalling of neurotransmitters.

40
Q

Recreational drugs can affect

A

Mood , cognition, perception, behaviour, movement, digestion, reproduction

41
Q

Addiction

A

Needing drug to feel normal

42
Q

Tolerance

A

Requiring more of the drug to feel an effect

43
Q

How is addiction caused

A

Addiction caused by repeated use of antagonists. Blockage of receptors causes the postsynaptic neuron to make more receptors and they become more sensitive. sensitisation !!

44
Q

How is tolerance caused

A

Tolerance caused by repeated use of agonists. Repeated activation of receptors causes Presynaptic neuron to lower their number. This means larger amount of drug needed for same effect. Desensitisation

45
Q

Tolerance example

A

Alcohol

46
Q

Addiction example

A

Ketamine

47
Q

Sensitisation

A

Number of receptors increase

48
Q

Desentisisation

A

Number of receptors decrease

HUMAN BIO (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions