Module 1.2: Nervous System

Question 1

What is the nervous system?

Answer 1

It is the body’s speedy, electrochemical communication network, consisting of all nerve cells

Question 2

What is the nervous system divided based on?

Answer 2

Function

Question 3

What is the main division of the nervous system?

Answer 3

Central = brain and spinal cord
Peripheral = rest of the body

Question 4

What is the peripheral nervous system?

Answer 4

Sensory and motor neurons that connect to CNS

Question 5

What is the peripheral nervous divided into? What are they each in charge of?

Answer 5

1. Autonomic Nervous System - controls involuntary functions (i.e. digestion, heartbeat, breathing)
2. Somatic Nervous System - controls voluntary functions

Question 6

What is the autonomic nervous system split into? What does each control?

Answer 6

1. Sympathetic Nervous System - fight or flight response
2. Parasympathetic Nervous System - rest and digest (slows the body down after a stressful event)

Question 7

What does the sympathetic nervous system do when activated?

Answer 7

Automatically
- accelerates heart rate
- dilates pupils
- slows down digestion, inhibiting peristalsis
- inhibits salivation
- relaxes bronchi (to breathe deeper)
- stimulates glucose production and release in liver
- secretes adrenaline and noradrenaline from adrenal glands
- inhibits bladder contraction

Question 8

What does the parasympathetic nervous system do when activated?

Answer 8

Automatically
- constricts pupils
- stimulates saliva flow
- constricts bronchi
- slows heartbeat
- stimulates peristalsis and secretion
- stimulates bile release
- contracts bladder

Question 9

What neurons/ nerves does the somatic nervous system consist of?

Answer 9

Afferent nerves = sensory neurons (receive information from PNS and transfer them to CNS)
Efferent nerves = motor neurons (receive information from CNS and transfer them to PNS)

Question 10

What are interneurons?

Answer 10

The neurons in the brain and spinal cord that serve as an intermediary between sensory and motor neurons; carry info around the brain for processing

Question 11

What are reflexes?

Answer 11

Automatic responses to stimuli

Question 12

Some reactions occur quicker than others. When does this happen?

Answer 12

spinal reflex arc - When the sensory neurons reach just the spinal cord, which responds immediately (usually in instances of harm/pain)

Question 13

What does the enteric nervous system do?

Answer 13

It directly controls the gastrointestinal tract (GI tract), pancreas, and gallbladder; contains efferent, afferent, and interneurons