Nervous System

Question 1

What are the two main jobs of the nervous system?

Answer 1

1. To collect and respond to information in the environment.
2. To control the working different organs and cells in the body (including the brain )

Question 2

What is the structure of the nervous system?

Answer 2

The nervous system → CNS (central nervous system) → spinal cord + brain
→ peripheral → autonomic + somatic
→ autonomic → sympathetic + parasympathetic

Question 3

What is the function of the CNS?

Answer 3

To coordinate incoming sensory information and respond to it by sending appropriate instructions to other parts of the nervous system. It also contains all of our thinking, memory, decision making and language.

Question 4

What is the function of the peripheral nervous system?

Answer 4

Divided into two parts:

Somatic nervous system - consists of motor and sensory neurons - Controls all voluntary actions of the body, and collects information, both from the outside world and our internal organs and sends instructions to the CNS.

Autonomic nervous system - governs autonomic functions in the body, e.g. fight or flight - Controls all involuntary actions in the body. Coordinates functions of the body that are vital for survival. For example, your hand will move away something hot without having to think about it.

Question 5

What are the 2 branches of the autonomic system and what are the purpose?

Answer 5

The sympathetic branch - Sets off arousal, which can be mild like a feeling of anxiety or extreme like the fight or flight response. It is activated when we are ‘under threat’

The parasympathetic branch - Allows the body to store up energy when we are not ‘under threat’

Therefore, the ANS is the part of the nervous system that helps us react in an emergency. It also has functions that controls our breathing, heart rate and homeostasis.

Question 6

What are the steps of fight or flight?

Answer 6

1. The hypothalamus detects a threat and triggers activity in the sympathetic branch of the autonomic nervous system, this moves us from resting state to arousal.
2. The stress hormone, adrenaline, is then released from the adrenal glands into the bloodstream.
3. This triggers physiological changes in the body.
4. Finally, once the threat has passed, the parasympathetic nervous system acts as a ‘break’ and returns the body to resting state.

Question 7

What are some of the physiological changes that happen during arousal and what is the reason for it?

Answer 7

Increased heart rate - Makes the person more aware
Pupils dilate - Helps focus on surroundings
Sweaty palms - Cools body down
Pale skin - Blood rushing around the body

Question 8

What are the parts of a neuron?

Answer 8

Dendrites, axon, myelin sheath, cell body, axon terminal

Question 9

What is the function of dendrites?

Answer 9

Branches that stick out the neurons that receive signals from other neurons

Question 10

What is the function of the axon?

Answer 10

Carries impulses away from the cell body for it to be passed onto the next neuron.

Question 11

What is the function of the myelin sheath?

Answer 11

Fatty layer that protects the axon and speeds us electrical transmission down the axon

Question 12

What is the function of the cell body?

Answer 12

Includes the nucleus which contains genetic material of the cell.

Question 13

What is the function of the axon terminal?

Answer 13

They are at the very end of the axon that contains neurotransmitters and make synoptic contact with the next neuron in the chain.

Question 14

What are the 3 types of neurons?

Answer 14

Sensory, relay and motor

Question 15

Identify the differences between the relay, motor and sensory neuron.

Answer 15

https://tutor2u-net.imgix.net/subjects/psychology/studynote-images/psych-biopsych-sensory-motor-relay-neurons.png?auto=compress%2Cformat&fit=clip&q=80&w=800

Question 16

Label the basic parts of the neuron.

https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.brainframe-kids.com%2Fbrain%2Fprintables%2Fb-diagram-cells-neuron.htm&psig=AOvVaw1qL2uORucxdPgXxoEr4Q9V&ust=1698852999441000&source=images&cd=vfe&opi=89978449&ved=0CBEQjRxqFwoTCKjvp97OoIIDFQAAAAAdAAAAABAE

Answer 16

https://www.simplypsychology.org/wp-content/uploads/Parts-of-a-Neuron-Cell.png

Question 17

What is the function of the sensory neuron?

Answer 17

→ They send messages from the body to the brain
→ when these nerve impulses reach the brain, they are translated into ‘sensations’ such as vision, hearing, taste and touch.
→ not all sensory neurons reach the brain, as some stop at the spinal cord for quick reflex actions

Question 18

What are the functions of the relay neurons?

Answer 18

→ found in the brain and spinal cord
→ send messages between the sensory and motor neurons

Question 19

What is the function of the motor neuron?

Answer 19

→ found in the CNS and controls muscle movement
→ they send messages from the brain to the body ( tells relevant body parts to move)

Question 20

What is the process of the synaptic transmission?

Answer 20

• A message is passed down the axon of the neuron as an electrical impulse (action potential)
•once the action reaches the end of the axon it needs to be transferred to another neuron ar tissue. To do this, it must cross over the synaptic gap between the presynastic Nelson and post-synaptic neuron.
• At the end of the neuron are the synaptic vesicles, which contain chemical messengers, known as neurotransmitters
• When the electrical impulse reaches the synaptic vesicles, they release their contents of neurotransmitters.
• Neurotransmitters then carry the signal across the synaptic gap. They bind to the receptor sites on the post-synaptic cell, thereby completing the process of synaptic transmission.

Question 21

Draw and label a diagram of the process of synaptic transmission.

Answer 21

https://www.simplypsychology.org/wp-content/uploads/Chemical-synapse.png

Question 22

What is excitation and inhibition?

Answer 22

-Neurotransmitters can either have an inhibitory or excitatory effect:
-Excitatory neurotransmitters make the post-synaptic cell more likely it fire and pass on the message to the next cell.
-Inhibitory neurotransmitters make the post-synaptic cell less likely to fire. These cause the message to be stopped at the post synaptic membrane and generally have a calming effect on the body.

(think of it like pedals on a car - Excitatory are the accelerator and inhibitory are the break)

Question 23

What are the 2 main functions of the endocrine system?

Answer 23

1. To secrete the hormones which are required to regulate many bodily functions.
2. To provide a chemical system of communication via the blood stream.

Question 24

What are some examples of glands of the endocrine system and the hormone they release?

Answer 24

Adrenaline gland - Releases adrenaline
Thyroid gland - Releases thyroxine
Ovaries - Produce oestrogen and progesterone