The Nervous Sytem

Question 1

What is the CNS?

Answer 1

Central nervous system.
Brain and spinal cord.
Acts as the body’s control centre, processing sensory information and directing responses.

Question 2

What is the PNS?

Answer 2

Peripheral nervous system.
Connects CNS to the rest of the body.
Transmits messages from the CNS to the rest of the body.

Question 3

What are the 3 parts of neural communication?

Answer 3

-sensory nerves collected info from body and send it to the brain via spinal cord.
-the brain processes this info and sends messages back to the spinal cord via body.
-the communication within the brain and along the spinal cord happens through neurons.

Question 4

What is the cell body (soma)?

Answer 4

Central part of the neuron containing the nucleus.
Maintains cell health and produces necessary proteins.

Question 5

What are dendrites?

Answer 5

Part of a neurone.
Branch-like structured extending from the soma.
Receive chemical signals from other neurones and convert them into electrical impulses.

Question 6

What is the axon?

Answer 6

Part of a neurone.
Long stand of projection from the cell body.
Conducts electrical impulses away from the cell body toward other neurones, muscles or glands.

Question 7

What is the axon hillock?

Answer 7

Region where the axon connects to the cell body.
Initiates action potentials (nerve impulses) if the signal is strong enough.

Question 8

What is the myelin sheath?

Answer 8

Part of a neurone.
Layer of fatty substances acting as an insulator.
Increases speed of electrical impulse transmission along the axon.

Question 9

What are nodes of ranvier?

Answer 9

Gaps in the myelin sheath along the axon.
Allows impulses to ‘jump’ from one node to the next to enable rapid signal transmission.

Question 10

What are axon terminals?

Answer 10

Branches at the end of the axon.
Releases neurotransmitters into the synapse to communicate with the next neuron or target cell.

Question 11

Where are terminal buttons located?

Answer 11

At the end of axon terminals.

Question 12

Where is the amygdala located and what does it do?

Answer 12

Located in the temporal lobe near the base of the skull just above the ear.
It acts as an emotional alarm.
Processes strong emotions like fear/anger.
The right ride evokes fear/sadness and the left side acts as a reward system with positive and negative emotions.

Question 13

Where is the hippocampus located and what does it do?

Answer 13

Located in the medial part of the temporal lobe.
Acts as a memory centre, converts STM into LTM by organising, storing and retrieving memories within your brain.

Question 14

Where is the hypothalamus located and what does it do?

Answer 14

Located in the mid brain under the thalamus.
Controls vital functions like hunger, thirst and body temp.
Essential for maintaining homeostatis.

Question 15

Where is the corpus callosum located and what does it do?

Answer 15

Located in the centre of the brain between left and right hemispheres (the brains bridge that connects left and right)
Important for coordinating movements and processing complex information like spatial awareness and language.

Question 16

Where is the lambic system located and what does it do?

Answer 16

Located beneath the cerebral cortex’s, the brains outer layer and is above the brain stem.
An emotional and memory processor.
It is involved in how we form memories and experience emotions.
It includes: hypothalamus, hippocampus, amygdala.

Question 17

Describe dopamine.

Answer 17

-Related to emotional and cognitive functions as well as posture and control of movement.
-It reinforces behaviours that result in award.
-Contributes to feelings of alertness/focus/motivation/happiness.
-Helps with Mood regulation/sleep, digestion and blood flow.

Low dopamine-Parkinson’s high dopamine-obesity, addiction.

Question 18

Describe serotonin.

Answer 18

Plays a significant role in mood regulation.
Helps with sleep/modulating mood.
Regulate anxiety/reduce depressed feelings.
Required in the gut, promotes healthy digestion.

Question 19

Describe noradrenaline.

Answer 19

-It works with adrenaline to increase heart rate and amount of blood pumping from the heart.
-Associated with emotion like danger usually throughout the day.
-Gives you more energy to pay attention and wakes you up.

High-anxiety, difficulty sleeping.
Low-depression, poor memory.

Question 20

Describe acetylcholine.

Answer 20

-Stimulates muscle contractions and has a key function in motor control and movement.
-necessary for memory and other cognitive functions such as attention and wakefulness/alertness.
-involved in expressions of some emotions such as anger and sexuality.

Question 21

What is the start of Synaptic transmission?

Answer 21

An action potential reaches the axon terminal, triggering the release of neurotransmitters from the presynaptic cleft into the presynaptic membrane and releases contents info the synaptic cleft.

Question 22

What happens in the middle part of synaptic transmission?

Answer 22

Neurotransmitters interact with receptors on the postsynaptic membrane, they bind to these receptors and can cause an action to occur in the post synaptic cell as a result.

Question 23

What 3 ways can neurotransmitters be cleared from the synaptic cleft?

Answer 23

-some will drift away through diffusion.
-some can be taken back up into the presynaptic neuron in a process called reuptake.
-enzymes break down the neurotransmitter within the synaptic cleft, then component parts of the neurotransmitter can be sent back into the presynaptic neurone to make more neurotransmitters.