Brainscape's Knowledge GenomeTM

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


See full index

Higher Biology > Neurobiology Unit 3 KA 4 > Flashcards

Neurobiology Unit 3 KA 4 Flashcards

Cells of the Nervous System and Neurotransmitters at synapses

1
Q

What are Neurons?

A

Neurons are nerve cells which receive and transmit nervous impulses

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

What makes up Neurons? (3)

A

1) Several Dendrites
2) A cell body
3) One axon

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

What direction does a nervous impulse travel down a Neuron?

A

Dendrites -> Cell body -> Axon

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

What does the cell body of a Neuron contain? (3)

A

1) The nucleus
2) Most of the cytoplasm
3) Ribosomes

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

What does the cell body of a Neuron do?

A

The cell body of a neuron is the control centre of the cells metabolism

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

What is an Axon?

A

An Axon is a single nerve fibre that carries nerve impulses away from a cell body and towards the next neuron/muscle/gland

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

What surrounds an Axon?

A

The Myelin sheath surrounds an Axon

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

What does the Myelin sheath do?

A

The Myelin sheath insulates the Axon and increases the speed of impulse conduction

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

What does Multiple sclerosis (MS) do to the Myelin sheath?

A

Multiple sclerosis destroys the Myelin sheath and causes a loss of co-ordination and muscle control is severely impaired

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

What do Glial cells do? (2)

A

1) Produce the Myelin sheath
2) Physically support neurons

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

What is a Synapse?

A

A Synapse is the tiny region between the axon end of one neuron and the dendrite end of the next neuron

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

What is the Neuron before a Synaptic cleft called?

A

The neuron before a Synaptic cleft is called the pre-synaptic neuron

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

What is the Neuron after a Synaptic cleft called?

A

The neuron after a Synaptic cleft is called the post-synaptic neuron

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

What happens to a Neurotransmitter (NT) at a synapse? (5)

A

1) The impulse travels down the axon of the pre-synaptic neuron
2) The impulse arrives at vesicle
3) NT’s stored in vesicles are released into the cleft
4) NT’s diffuse across the cleft
5) NT’s bind to the receptors on the membrane of the post-synaptic neuron

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

What do Receptors determine?

A

Receptors determine whether the signal is excitatory or inhibitory

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

Why do Vesicles containing Neurotransmitters occur on only one side of a synapse?

A

Vesicles containing Neurotransmitters only occur on one side of a synapse because it ensures that the nerve impulses are transmitted in only one direction

17
Q

Why must Neurotransmitters be removed from the synaptic cleft after the impulse has been transmitted?

A

Neurotransmitters must be removed from the synaptic cleft after the impulse has been transmitted to prevent the continuous stimulation of post-synaptic neurons

18
Q

How can Neurotransmitters be removed from a synaptic cleft? (2)

A

1) Enzyme degradation
2) Re-uptake

19
Q

What is Enzyme degradation?

A

Enzyme degradation involves breaking down the NT into non-active products which are reabsorbed by the pre-synaptic neuron and resynthesized into the active neurotransmitter (requires energy)

20
Q

What is Re-uptake?

A

Re-uptake is when Neurotransmitters are reabsorbed directly by the pre-synaptic membrane that secreted it and is stored in the vesicle ready for use

21
Q

What does an Excitatory effect do to a muscle?

A

An Excitatory effect causes a muscle to contract

22
Q

What does an Inhibitory effect do to a muscle?

A

An Inhibitory effect causes a muscle contraction to release

23
Q

What must happen in order for an impulse to be transmitted?

A

In order for an impulse to be transmitted, a minimum number of Neurotransmitter molecules must attach to receptors to reach the minimum threshold on the post-synaptic neuron

24
Q

What happens when the secretion of Neurotransmitters is insufficient?

A

If the secretion of Neurotransmitters is insufficient it allows the synapses to filter out the weak stimuli

25
Q

Why are Mitochondria present in a Neuron?

A

Mitochondria are present in a Neuron to ensure there is enough energy for reabsorption of NTs from the synaptic cleft

26
Q

What is Summation?

A

Summation is when a series of weak stimuli can release enough NT to trigger an impulse

27
Q

What are Endorphins?

A

Endorphins are NTs that stimulate neurons involved in reducing the sensitivity of pain (natural painkillers)

28
Q

What increases Endorphin production? (4)

A

1) Severe injury
2) Prolonged and continuous exercise
3) Stress
4) Certain foods (chocolate)

29
Q

Increased levels of Endorphins are linked to feelings of pleasure gained from what three activities?

A

1) Eating
2) Sex
3) Prolonged exercise

30
Q

What is Dopamine?
What does it activate?

A

Dopamine is a NT that induces the feeling of pleasure and reinforces that particular behaviour by activating the Reward pathway in the brain

31
Q

What does the Reward pathway involve?

A

The Reward pathway involves neurons which secrete or respond to dopamine

32
Q

How is the Reward pathway activated?

A

The reward pathway is activated when an individual engages in behaviour that is beneficial to them (eating when hungry)

33
Q

Name two NT related disorders -

A

1) Alzheimers disease
(loss of neurons that synthesise Acetylcholine)
2) Parkinson’s disease
(loss of neurons that synthesise dopamine)

34
Q

What do Antagonistic drugs do?

A

Antagonistic drugs contain chemicals that bind to specific receptors blocking the action of the neurotransmitter at a synapse

35
Q

What do Agonist drugs do?

A

Agonist drugs contain chemicals that bind to and stimulate specific receptors mimicking the action of the neurotransmitter at a synapse

36
Q

What do Recreational drugs affect?

A

Recreational drugs affect the transmission of nerve impulses in the reward circuit of the brain

37
Q

What can Recreational drugs change? (4)

A

1) Mood (happy/confident/aggressive)
2) Cognition thinking(Poorer at problem solving and decision making)
3)** Perception** (misinterprets stimuli- colour, sound, time)
4)** Behaviour **(stay awake longer, talk endlessly)

38
Q

What causes drug Addiction?

A

Drug Addiction is caused by the repeated use of Antagonists - Antagonists block specific receptors increasing their sensitivity and the person craves more of the drug

39
Q

What causes drug Tolerance?

A

Drug Tolerance is cause by the repeated use of Agonists - Agonists stimulate specific receptors decreasing their sensitivity and the person must take more of the drug to get an effect

Higher Biology (24 decks)

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