Nervous system

Question 1

Sense organs receive chemical and physical information from what?

Answer 1

The environment

Question 2

After sense organs receive information from the environment they do what?

Answer 2

Transmit what they have received to the nervous system which then processes the information and makes decisions to react appropriately.

Question 3

Describe the brain.

Answer 3

• Made of 2 hemispheres
• Controls each hemisphere by the opposite side of the body
• Composed of gray matter (top) and white matter (inside)
• Site of intellectual faculties

Question 4

What does gray matter do?

Answer 4

Processes information

Question 5

What does white matter do?

Answer 5

Transmits information through nerve impulses

Question 6

How does the brain stimulate muscles?

Answer 6

analyzes and makes sense of information (nerve impulses) from the senses and it produces nerve impulses to stimulate muscles

Question 7

Describe the cerebellum.

Answer 7

• Similar composition to the brain
• Sits right under the brain
• Controls balance and motion
• Receives information on movements that a person wants to make and then analyzes body and muscle position, along with balance information from the inner ear to allow that movement to happen

Question 8

Describe the brain stem.

Answer 8

• Positioned under the brain
• Connects the brain to the spinal cord
• Controls vital organs
• Acts as a gateway between the brain and the spinal cord

Question 9

Describe the spinal cord.

Answer 9

• Long string of nerves
• Extends from the brain stem to the lower back
• Protected by the spine
• Transmits messages from the brain to the motor nerves
• Transmits information from the sensory nerves to the brain

Question 10

What are motor nerves?

Answer 10

Nerves responsible for movement

Question 11

What are sensory nerves?

Answer 11

Nerves associated to the senses

Question 12

What makes up the central nervous system?

Answer 12

• Brain
• Cerebellum
• Brain stem
• Spinal cord

Question 13

What makes up the Peripheral nervous system?

Answer 13

All of the nerves in the body

Question 14

Cranial nerves are connected to what?

Answer 14

The brain, cerebellum, and brain stem

Question 15

Spinal nerves are connected to what?

Answer 15

The spinal cord

Question 16

Sensory nerves do what?

Answer 16

Carry nerve impulses from the sensory organs to the brain or spinal cord.

Question 17

What do motor nerves do?

Answer 17

Transmit nerve impulses from the central nervous system to the muscles.

Question 18

What are neurons?

Answer 18

They are cells of the brain, spinal cord, and nerves

Question 19

What do neurons do when stimulated?

Answer 19

They transmit electrical impulses (nerve impulses)

Question 20

What are neurons composed of?

Answer 20

A cell body surrounded by a cell membrane and containing organelles, along with the nucleus in the middle

Question 21

What are dendrites?

Answer 21

Small branches that receive nerve impulses from a previous neuron or sensory nerve.

Question 22

What does the axon do?

Answer 22

Sends nerve impulses out of the cell body and is tipped with nerve endings

Question 23

What are axons covered with?

Answer 23

An insulator called the myelin sheath which protects and channels the nerve impulse.

Question 24

What are synapses?

Answer 24

Neurons communicate with each other through gaps where information can be transferred from neuron to muscle or from neuron to neuron. This contact zone is called a synapse.

Question 25

How does a neuron react when it receives a stimulus through its dendrites?

Answer 25

It reacts by sending out an electrical current (nerve impulse)

Question 26

How do dendrites produce their own nerve impulse?

Answer 26

A. Neuron receives a stimulus through its dendrites and reacts by sending out an electrical current
B. The nerve impulse travels through the axon until it reaches the nerve endings
C. Small bags of neurotransmitters open at the surface of the endings and spread their chemical message into the synapse.
D. The dendrite of the next neuron receives this message and produces its own nerve impulse.

Question 27

How do chemicals stimulate a muscle to make it contract?

Answer 27

A. Neuron receives a stimulus through its dendrites and reacts by sending out an electrical current
B. The nerve impulse travels through the axon until it reaches the nerve endings
C. Small bags of neurotransmitters open at the surface of the endings and spread their chemical message into the synapse.
D. The chemicals stimulate a muscle allowing it to contract.