A & P Introduction to Nervous system

Question 1

List the 3 functions of the nervous system

Answer 1

(1) Sensory (2) 
Integration and (3) Motor

Question 2

Describe Sensory from the nervous system

Answer 2

Sensory: detect stimuli
Stimuli can be either:
a) External: originating outside of the body. Examples: a bug
walking across your skin or light entering your eye
b) Internal: originating inside of the body. Examples: change in body
temp or change in amount of CO2 in the blood
Also called: sensory input

Question 3

Describe Integration form the nervous system

Answer 3

Integration: processes & interprets sensory input.
Process means information is sent to the correct area of the central
nervous system (CNS) For example: sensory information from the eyes is
sent to the visual area of the brain which is in the occipital lobe (as we will
learn next week).
Interprets means to decide if action (response) is needed. Not all stimuli
requires a response, though

Question 4

Describe Motor from the nervous system

Answer 4

Motor: response to stimuli
Activates effectors organs which can be muscles (smooth, skeletal, or
cardiac) or glands (like the pancreas and salivary glands)
Also called: motor output

Question 5

Name the two parts of the Nervous system

Answer 5

Central nervous system (CNS) and Peripheral nervous system (PNS)

Question 6

Describe the Central nervous system

Answer 6

Made of: brain and spinal cord
Functions: Receives sensory input, integrates and processes the
information

Question 7

Describe the Peripheral nervous system

Answer 7

Made of: nervous tissue outside of CNS which are the spinal nerves,
cranial nerves, and sensory receptors
Functions: detects stimuli, sends sensory input to CNS, and performs the
motor response; Links body to CNS

Question 8

List and describe the two division of PNS

Answer 8

1) Sensory (afferent) division: takes info from sensory receptors to CNS
2) Motor (efferent) division: takes info from CNS to effector organs

Question 9

List and describe the 2 parts of motor (efferent) division

Answer 9

1) Somatic nervous system (SNS): voluntary nervous system
Controls: skeletal muscles
2) Autonomic nervous system (ANS): involuntary nervous
system
Controls: smooth muscle, cardiac muscle, & glands. Text
calls this the “visceral motor division”

Question 10

Define: Sympathetic

Answer 10

Fight or flight system

Question 11

Define: Parasympathetic

Answer 11

Resting or digesting system

Question 12

What does generate mean for action potential

Answer 12

Generate means they create the action potential

Question 13

What does conduct mean for action potential

Answer 13

conduct means they send it along their

membrane & eventually to another cell

Question 14

Characteristic of neurons

Answer 14

1) Can’t reproduce (cannot undergo mitosis)
2) Have a long life (most nerve cells live as long as you do)
3) High metabolic activity. Need a lot of O2 and energy
4) Limited ability to regenerate (heal). CNS neurons can’t regenerate at all
because they cannot undergo mitosis. PNS neurons can under specific
circumstances but regeneration is often flawed

Question 15

What are the two parts of neuron

Answer 15

Cell body and Processes

Question 16

Describe cell body and its function

Answer 16

Cell body also called soma or neurosoma
-the central or “fat” part of a neuron. Contains the nucleus, most of
the organelles, & a lot of cytosol
Function: this is the control center where integration and processing
takes place

Question 17

In the CNS the cell body is known as

Answer 17

Nuclei

Question 18

In the PNS the cell body is known as

Answer 18

Ganglia

Question 19

Describe the Processes and its functions

Answer 19

these project from the cell body. These are also called nerve
fibers. Contain a small amount of cytosol & some organelles
Function: communication. Send information to and from the cell body
Some neurons have their processes in the CNS while others have
them in the PNS

Question 20

Tract is the process called in which nervous system

Answer 20

Central nervous system

Question 21

Nerve is the process called in which nervous system

Answer 21

Peripheral nervous system

Question 22

Name the two types of processes

Answer 22

Dendrites and axon

Question 23

Define Dendrites and describe its structure and function

Answer 23

Dendrite: is the “receiving end” of a neuron because it receives information
from another neuron or from a sensory organ/receptor
- Function of dendrite: sends this information to the cell body
Info is in form of a graded potential
- Structure of dendrite: short, tapering, & branched.
- A neuron has a lot of dendrites. Having a lot allows it to communicate with a lot of other cells

Question 24

Define Axon and describe its structure and function

Answer 24

Axon is the “sending end” of a neuron because it sends information to
another neuron or to the effector organ
- Functions of axon: generates AP and conducts the impulse away from the
cell body
-Structure of axon: very long and has few or no branches.
- A neuron only has one axon

Question 25

Define: neuroglia (glial) cells

Answer 25

these are supporting cells; they provide support and protection to the nerve cells.

Question 26

What glial cell produce myelin sheath

Answer 26

Oligodendrites