Chapter 34:Nervous System

Question 1

Name two main parts of the central nervous system in humans

Answer 1

Brain ,spinal cord

Question 2

Difference between CNS and PNS

Answer 2

The CNS is made up of brain and spinal cord while the PNS is the network of nerves in the rest of the body.

Question 3

What is a neuron

Answer 3

a nerve cell

Question 4

Name the three types of neurons

Answer 4

Sensory Neurons
Interneurons
Motor Neurons

Question 5

What does PNS stand for?

Answer 5

Peripheral Nervous System

Question 6

What does CNS stand for?

Answer 6

Central Nervous System

Question 7

What are sensory neurons?

Answer 7

They carry impulses from receptors to sense organs to the CNS

Question 8

What are motor neurons?

Answer 8

They carry impulses from CNS to effector organs.

Question 9

What are interneurons?

Answer 9

They carry information between sensory and motor neurons

Question 10

What is the function of the dendrite?

Answer 10

carry impulses towards cell body

Question 11

What is the function of the axon?

Answer 11

carry impulses from cell body

Question 12

What is the function of the cell body?

Answer 12

forms neurotransmitter chemicals

Question 13

What is the function of the schwaan cell?

Answer 13

forms neurotransmitter chemicals

Question 14

What is the function of the myelin sheath?

Answer 14

insulates the electrical impulses

Question 15

What is the refractory period?

Answer 15

Neuron must recover for a fraction of a second before it can transmit again

Question 16

What is the all or nothing effect?

Answer 16

If a stimulus is too weak or does not meet the threshold the nerve impulse is not carried.

Question 17

What is a synapse?

Answer 17

a region where two neurons come into close contact.

Question 18

What is the function of the synapse?

Answer 18

Transmit impulse

Control the direction of the impulse

Question 19

How does the nervous system work?

Answer 19

1. Stimulus detected
2. Message passes along neurons
3. Messages are processed
4. Neurons stimulate the muscles/gland to respond

Question 20

What is a nerve impulse?

Answer 20

An electrical impulse caused by the flow of ions across the membrane which travels along the dendrites and axon to the neurotransmitter swelling.

Question 21

How does a nerve impulse work?

Answer 21

1. The nerve impulse reaches the Threshold.
2. The inside of the axon becomes positive and the outside becomes negative.
3. Energy is supplied to the nerve impulse.
4. Refractory Period occurs.

Question 22

What happens near the synapse?

Answer 22

1.Neurotransmitter molecules released into synaptic cleft
2.They diffuse across the cleft and bind to receptors on the post-synaptic neuron.
3.Neurotransmitter molecules are rapidly broken down by enzymes and then reabsorbed by the pre-synaptic neuron
.

Question 23

Examples of Neurotransmitters:

Answer 23

Acetylcholine
Noradrenaline
Dopamine
Serotonin

Question 24

What is a synaptic cleft?

Answer 24

is the tiny gap between two neurons at a synapse

Question 25

What protects the brain?

Answer 25

meninges cerebrospinal fluid skull

Question 26

What is the function of cerebrum?

Answer 26

``` Movement Intelligence Emotion Receiving Information From Sense Organs language Personality ```

Question 27

Cerebellum

Answer 27

Motor Movement Coordination Balance Walking

Question 28

Medulla Oblongata

Answer 28

Involuntary processes Hearbeat Breathing Blood Pressure

Question 29

Hypothalamus

Answer 29

``` Homeostasis Body Temperature Hunger Thirst Sleep Osmoregulation ```

Question 30

Pituitary Gland

Answer 30

Hormones

Question 31

Nervous System Disorder

Answer 31

Name:Parkinsons Cause:the failure to produce a muscle neurotransmitter called dopamine in a part of the brain which results in failure to control muscle contraction Symptoms:Trembling in hands and legs,stiffness and weakness Treatment:Physiotherapy

Question 32

How the spinal cord protected?

Answer 32

Vertebrae | meninges

Question 33

What is in white matter?

Answer 33

axons

Question 34

What is in grey matter?

Answer 34

Dendrites and cell body

Question 35

Dorsal Root

Answer 35

contains sensory neurons

Question 36

Ventral Root

Answer 36

contains motor neurons

Question 37

Central Canal

Answer 37

contains cerebrospinal fluid

Question 38

What is Reflex Action?

Answer 38

It is an automatic,involuntary,unthinking response to a stimulus.

Question 39

Examples Reflex Action:

Answer 39

blinking | gag reflex

Question 40

Advantage of Reflex Action

Answer 40

Fast response so protect the body from damage