Chapter 2 : The nervous system

Question 1

What are the two divisions of the Nervous system?

Answer 1

The Central Nervous system (CNS)
Peripheral Nervous system (PNS)

Question 2

What makes up the CNS?

Answer 2

The brain and the spinal chord

Question 3

What are the two divisions of the Peripheral nervous system?

Answer 3

The Somatic nervous system and the Autonomic nervous system

Question 4

What is the role of the spinal chord?

Answer 4

The spinal chord transmits sensory information from the Peripheral nervous system to the brain. It also sends motor messages from the brain down the spinal chord to the PNS

Question 5

What is the role of the brain?

Answer 5

The brain is a mass of neurons responsible for how we think, feel and how we react to the world around us. The brain coordinates all activities of the nervous system and communicates information through the spinal chord

Question 6

How does the brain receive sensory information?

Answer 6

The spinal chord receives sensory information from the PNS and transmits it along ascending tracts up to the brain for further processing.

Question 7

How does the brain receive Motor information?

Answer 7

Motor information is sent from the brain and carried along descending tracts where it can then be relayed to muscles, organs and glands so they can react.

Question 8

What does the Peripheral nervous system do?

Answer 8

Conveys sensory information from the body’s internal and external environments to the CNS and transmit motor commands from the CNS to the rest of the body through the spinal chord

Question 9

What are the two subdivisions of the PNS

Answer 9

The somatic nervous system (SNS)
The autonomic nervous system (ANS)

Question 10

What responses are the somatic nervous system responsible for?

Answer 10

The SNS is responsible for voluntary responses

Question 11

How does the SNS receive sensory information?

Answer 11

receptor cells located throughout the body such as skin, joints, eyes and tongue

Question 12

What does the autonomic nervous system do?

Answer 12

The ANS controls involuntary activities, its responsible for the activity level of our internal organs such as heart beat, pupils dialating, stomach digestion ect.

Question 13

What are the three divisions of the ANS

Answer 13

Sympathetic nervous system
Parasympathetic nervous system
Enteric nervous system

Question 14

The parasympathetic nervous system acts as the body’s ______________

Answer 14

Car brakes

Question 15

What is the role of the sympathetic nervous system?

Answer 15

The SNS activates when we perceive a threat, when activated the bodys internal resources provide extra energy to help the body respond to the threat.

Question 16

What is the role of the parasympathetic nervous system?

Answer 16

The PNS has the opposite effect is maintains a level of homeostasis and brings the body back to a normal level of arousal after the sympathetic nervous system has been activated.

Question 17

What does the Enteric nervous system do?

Answer 17

Gut control: the enteric nervous system receives and sends messages to the sympathetic and parasympathetic nervous system, it also controls many functions of the digestive system.

Question 18

roles of the sympathetic nervous system include

Answer 18

Accelerating heart rate
Dialating pupils
inhibits digestion
relaxes bladder

Question 19

Is constricting pupils due to the sympathetic or parasympathetic nervous system?

Answer 19

parasympathetic

Question 20

Some roles of the parasympathetic nervous system include:

Answer 20

Slows heart rate
stimulates digestion
Constricts pupils
contracts bladder

Question 21

What controls involuntary muscles that regulate internal organs?

Answer 21

The autonomic nervous system

Question 22

What is a spinal reflex?

Answer 22

an unconscious response that occurs independently of the brain, they are essential for survival and automatic.

Question 23

What happens when someone steps on a nail?

Answer 23

Initially, an intense sensation is detected in your foot by a sensory receptor. Instantly, the sensory receptor fires off a message via the sensory neurons to your spinal cord and activates an interneuron, which in turn transmits a message via the motor neurons, causing your leg muscles to contract and allowing you to withdraw your foot from the sharp nail.

Question 24

What is a neuron?

Answer 24

Neurons make up the nervous system, they receive process and transmit information all around the body.

Question 25

what do dendrites do?

Answer 25

Receive neurotransmitters from other neurons and convert into action potential to then send a message to the soma

Question 26

What are 'locks'?

Answer 26

The receptor site in the postsynaptic membrane that has a specific shape to fit a certain neurotransmitter.

Question 27

What are 'keys'?

Answer 27

The neurotransmitters which fit into specific receptor sites.

Question 28

A primary excitatory neurotransmitter, involved in high speed neural transmission.

Answer 28

Glutamate

Question 29

What happens when glutamate is released?

Answer 29

When glutamate is released at the synapse it binds to a glutamate receptor site located on the postsynaptic neuron. As a result it activates these receptor sites and makes it more likely for the postsynaptic neuron to fire an action potential.

Question 30

What is the primary inhibitory neurotransmitter?

Answer 30

GABA

Question 31

How does GABA work?

Answer 31

GABA calms and slows neural transmission, when GABA activates receptor sites, the cells that have those receptors are inhibited and therefore less likely to fire an action potential.

Question 32

What is the difference between neurotransmitters and neuromodulators?

Answer 32

Neurotransmitters are fast acting and short lived. Neuromodulators are slow acting but long lasting and can affect a large number of neurons at the same time.

Question 33

What is the main role of dopamine?

Answer 33

important in motivating behaviour in search of rewards, in learning how to predict when rewards are likely and in initiating movements.

Question 34

What does serotonin influence?

Answer 34

Pain, mood and sleep

Question 35

What are the two main neuromodulators?

Answer 35

Seretonin and Dopamine

Question 36

Define learning

Answer 36

Learning begins at birth and continues throughout our lifetime. It enables us to function daily and adapt to changes that are constantly occurring in the world around us.

Question 37

Define memory

Answer 37

Memory is an active information processing system that receives, organises, stores and recovers information when needed. Memory begins as you take in information from both the internal and external environment via our senses. Our nervous system converts this sensory information into impulses of electrochemical energy and transmits it to our brain where it is processed, interpreted and stored for future use.

Question 38

What is synaptic plasticity?

Answer 38

Neural plasticity that occurs in the synapse, leading to either an increase or decrease in activity between neurons.

Question 39

The growth of new synaptic connections is...

Answer 39

sprouting

Question 40

Getting rid of existing neural connections

Answer 40

Pruning

Question 41

Explain long term potentiation

Answer 41

is a long-lasting strengthening of neural connections at the synapse as a result of repeated stimulations from a presynaptic to postsynaptic neuron during learning.

Question 42

a change to the connection between neurons that results in a long- lasting reduction in the strength of a neural response due to persistent weak stimulation.

Answer 42

Long term depression (LTD)

Question 43

Why is LTD good?

Answer 43

helps to weaken and prune back unused synapses (synaptic pruning) – or those that are not stimulated. By doing this the brain becomes more efficient and therefore so do the learning and memory processes.