Exam 4 review

Question 1

What does the central nervous system consist of?

Answer 1

brain and spinal cord

Question 2

What does the peripheral nervous system consist of?

Answer 2

sensory receptors and nerves

Question 3

What is the function of sensory nervous?

Answer 3

transmit incoming signals to the CNS

Question 4

What is the function of motor nerves?

Answer 4

transmit outgoing signals from the CNS

Question 5

What is the function of somatic nerves?

Answer 5

send signals to skeletal muscles

Question 6

What is the function of autonomic nerves?

Answer 6

send signals to internal organs (involuntary)

Question 7

What are the parts of the neuron?

Answer 7

cell body, dendrites, axon, and axon terminals

Question 8

Characteristics of the cell body?

Answer 8

• receives signals from other neurons
• contains organelles (nucleus, mitochondria, ribosomes)
• no centrioles = no mitosis

Question 9

Functions of dendrites?

Answer 9

receive incoming signals from other neurons or sensory receptors

Question 10

Functions of the axon?

Answer 10

sends outgoing signals to other neurons or organs

Question 11

Functions of axon terminals

Answer 11

release chemicals called neurotransmitters

Question 12

What are nerves?

Answer 12

bundles of axons

Question 13

Function of schwann cells?

Answer 13

wrap myelin around axon

Question 14

What is myelin?

Answer 14

fatty substance that insulates axons (rich in lipids and proteins)

Question 15

Function of astrocytes?

Answer 15

help form the blood-brain-barrier

Question 16

What does it mean when a neuron is polarized?

Answer 16

the neuron is more negatively charged inside than it is outside

Question 17

Can ions move into and out of cells directly through the phospholipid bi-layer of the cell membrane?

Answer 17

no, ion channels are required

Question 18

During depolarization, do Na+ or K+ ions enter or leave the neuron and does this cause the neuron to become more negatively charged or positively charged?

Answer 18

Na+ enters the neuron which causes the neuron to become more negatively charged. threshold is -60mV

Question 19

During repolarization, do Na+ or K+ ions enter or leave the neuron and does this cause the neuron to become more negatively charged or positively charged?

Answer 19

K+ enters the neuron which causes the neuron to become more negatively charged. threshold is -70mV (rest)

Question 20

Which occurs first, depolarization or repolarization?

Answer 20

depolarization

Question 21

What is the name for the axon between myelin?

Answer 21

node of ranvier

Question 22

A continuous conduction of electrical signals is which type of axon?

Answer 22

unmeylinated axon

Question 23

a saltatory conduction of electrical signals is which type of axon

Answer 23

myelinated axon

Question 24

The site of communication between a neuron and another neuron or a target cell is called what?

Answer 24

synapse