Sec 29.4

Question 1

What does the central nervous system include?

Answer 1

Brain and spinal cord

Question 2

What is the CNS composed of?

Answer 2

Interneurons

Question 3

What do interneurons do?

Answer 3

They receive signals from sensory neurons and relay and process them within the brain and spinal cord, which then pass signals in response.

Question 4

How are interneurons in the brain arranged?

Answer 4

Their cell bodies are clustered together (gray matter) on the outside of the brain, and their axons are clustered together (white matter) on the inside of the brain.

Question 5

How are interneurons in the spinal cord arranged?

Answer 5

Their cell bodies are clustered together (gray matter) on the inside of the brain, and their axons are clustered together (white matter) on the outside of the brain.

Question 6

What are meninges?

Answer 6

Three layers of connective tissue that surround and protect the brain. Between the layers are fluids that cushion the brain so that it will not bang against your skull.

Question 7

What are the 3 main structures of the brain?

Answer 7

Cerebrum, Cerebellum, and Brainstem

Question 8

What is the cerebrum?

Answer 8

It is the part of the brain that interprets signals from your body and forms responses (i.e. hunger, thirst, emotions, motion, and pain)

Question 9

What are hemispheres? and what information do they process?

Answer 9

They are the right and left halves of the cerebrum. Each half processes information from the opposite side of the body.

Question 10

What is the corpus callosum?

Answer 10

It is a thick band of nerves that connects the two hemispheres.

Question 11

What happens to a signal that travels through your body and spinal cord?

Answer 11

When the spinal cord brings the signal from the body, it crosses over to the opposite hemisphere in the corpus callosum.

Question 12

What is the cerebral cortex?

Answer 12

It is the outer layer of the cerebrum that interprets information from your sensory organs and generates responses.

Question 13

Why is the cerebral cortex’s size deceptive?

Answer 13

Because it is about as thick as a pencil but its folds give it a larger surface area than expected (large enough to hold more than 10 billion neurons)

Question 14

How are neurons in the cerebral cortex arranged?

Answer 14

They are arranged in groups that work together to perform specific tasks

Question 15

How is it divided by scientists?

Answer 15

It is divided into 4 lobes based on function

Question 16

What are the names of the 4 lobes?

Answer 16

Frontal lobe
Parietal lobe
Temporal lobe
Occipital lobe

Question 17

What does the frontal lobe do?

Answer 17

controls & coordinates:
- voluntary movement
- speech production
- personality
- reasoning
- judgement

Question 18

What does the parietal lobe do?

Answer 18

contains the sensory cortex which interprets & coordinates info about the sense of touch (multisensory information)

Question 19

What does the temporal lobe do?

Answer 19

carries out
- speech interpretation
- hearing
- plays a role in memory

Question 20

What does the occipital lobe do?

Answer 20

processes visual info

Question 21

What makes up the inside of the cerebrum (under the cerebral cortex)?

Answer 21

The limbic system
Thalamus
Hypothalamus

Question 22

What does the limbic system do?

Answer 22

It is involved in learning and emotions + includes the hippocampus and amygdala

Question 23

What does the thalamus do?

Answer 23

It sorts information from sensory organs and passes signals between the spinal cord and other parts of the brain.

Question 24

What does the hypothalamus do?

Answer 24

It gathers information about body temperature, hunger, and thirst and sends signals to help the body maintain homeostasis

Question 25

What is the cerebellum?

Answer 25

It is the part of the brain that coordinates movement, maintains posture an balance, and automatically adjusts the body to move smoothly

Question 26

What does the brain steam do?

Answer 26

It connects the brain to the spinal cord and controls the most basic activities required for life (i.e. breathing & heartbeat)

Question 27

What are the three major parts of the brain stem?

Answer 27

Midbrain, pons, and medulla oblongata

Question 28

What does the midbrain do?

Answer 28

It controls some reflexes (i.e. changing pupil size to control the amount of light entering the eye)

Question 29

What does the pons do?

Answer 29

It regulates breathing and passes signals between the brain and the spinal cord.

Question 30

What does the medulla oblongata do?

Answer 30

It connects the brain to the spinal cord and controls basic life-sustaining functions (i.e. heart function, vomiting, swallowing, and coughing.

Question 31

What does the spinal column consist of?

Answer 31

It consists of vertebrae, fluid, meninges, and the spinal cord

Question 32

What is the spinal cord?

Answer 32

It is a ropelike bundle of neurons that is about as wide as a thumb, and it connects the brain to the nerves found throughout the body.

Question 33

Why does the brain depend on the spinal cord?

Answer 33

Because the spinal cord is responsible for delivering messages to the proper muscles and nerves in the PNS

Question 34

What happens if the spinal cord is damaged?

Answer 34

Messages cannot move between the brain and the rest of the body, which results in paralysis

Question 35

What are reflexes?

Answer 35

They are involuntary movements

Question 36

What are reflex arcs?

Answer 36

They are nerve pathways that need to cross only two synapses before producing a response.

Question 37

Why do quick reactions occur?

Answer 37

Because the signal never has to travel up the spinal cord to the brain

Question 38

Why do reflex arcs play an important role in protecting the body from injury?

Answer 38

Because they intercept signals and react quickly instead of waiting for the signal of danger to travel to the brain and be interpreted then react

Question 39

What does the peripheral nervous system include?