Nervous system

Question 1

What is the main function of the nervous system?

Answer 1

It coordinates actions and sensory information by transmitting signals to and from different parts of the body

Question 2

What are the two main parts of the nervous system?

Answer 2

Central nervous system

Peripheral nervous system

Question 3

What does the central nervous system consist of?

Answer 3

CNS - brain and spinal cord

Question 4

Describe the peripheral nervous system

Answer 4

PNS - consists of mainly nerves that connect the CNS to every other part of the body

Question 5

What do you call nerves that transmit signals from the brain to the body?

Answer 5

motor or efferent nerves

Question 6

What do you call nerves that transmit signals from the body to the brain

Answer 6

sensory or afferent nerves

Question 7

The peripheral nervous system can be divided into what three subsystems?

And what are each of their functions?

Answer 7

PNS

1. somatic - conscious actions - voluntary movement (skeletal muscle)
2. autonomic - unconscious actions - internal organs (smooth muscle)
3. enteric - subdivision of autonomic (gastrointestinal tract)

Question 8

What two subsystems can the autonomic nervous system be divided into and what are their general roles?

Answer 8

ANS

1. sympathetic - fight or flight
2. Parasympathetic - rest and digest

Question 9

When a cell receives a synaptic signal from a neuron what are the three responses that could be triggered in the post-synaptic cell?

Answer 9

1. Excitement
2. Inhibition
3. Modulation

Question 10

What are the two broad categories of cells in the nervous system and what are their functions?

Answer 10

1. Neurons - transmit signals

2. Glial cells - provide structural and metabolic support

Question 11

What is the most fundamental function of a neuron?

Answer 11

They communicate with other cells via synapses

Question 12

Describe a neural synapse.

Answer 12

neural synapse - membrane-to-membrane junctions that contain molecular machinery that allows rapid transmission of signals, either electrical or chemical.

Question 13

What is an axon?

Answer 13

An axon is a protoplasmic protrusion that can extend to distant parts of the body and make thousands of synaptic contacts.

Question 14

What are nerves?

Answer 14

Nerves are bundles of axons that extend through the body

Question 15

Where are the majority of neurons found?

Answer 15

Most neurons are found in the brain and ganglia (centralized structures)

Question 16

What type of glial cells make up myelin and where are they found?

Answer 16

1. Oligodendrocytes - CNS

2. Schwann cells - PNS

Question 17

What is the function of myelin?

Answer 17

Myelin is a fatty substance that wraps around axons and provided electrical insulation which allows them to transmit action potentials more rapidly and efficiently

Question 18

What layers envelope the brain and spinal cord to protect it?

Answer 18

Meninges

1. Dura mater - tough and thick
2. Arachnoid mater - web-like cushion
3. Pia mater - delicate and contains blood vessels

Question 19

What are the three locations we find cell bodies?

Answer 19

1. Brain
2. Spinal Cord
3. Peripheral Ganglia

Question 20

What are the six most important functions of glial cells?

Answer 20

1. Support neurons/hold them in place
2. Supply nutrients to neurons
3. Insulate neurons electrically
4. Destroy pathogens
5. Remove dead neurons
6. Provide cues to direct axons to their targets

Question 21

What are the two colors of matter that the nervous system can be divided into?

Answer 21

1. Gray Matter - Cell bodies of neurons

2. White Matter - Myelinated axons

Question 22

What is the difference between a nucleus and a ganglion?

Answer 22

Both are clusters of cell bodies, but their locations differ.
- Nucleus - in brain
- Ganglion - in periphery
There are some exceptions (ie. basal ganglia)

Question 23

What are action potentials?

Answer 23

Action potentials are neural signals that propagate along an axon in the form of electrochemical waves to produce cell to cell signals at synapses.