Slide A

Question 1

Nervous system

Answer 1

Central nervous system
Peripheral nervous system

Question 2

Central nervous system

Answer 2

Brain
Spinal cord

Question 3

Peripheral nervous system

Answer 3

Cranial nerves (12)
Spinal nerves (31)

Question 4

Neurons

Answer 4

Specialized cells that carry “messages” through an electrochemical process

Question 5

Human brain has about

Answer 5

100 billion neurons

Question 6

Dendrites

Answer 6

Bring information to the cell body
Rough surface (dendritic spines)
Usually many dendrites per cell
Have ribosomes
No myelin insulation
Branch near the cell body

Question 7

Axons

Answer 7

Take information away from the cell body
Smooth surface
Generally only 1 axon per cell
No ribosomes
Can have myelin
Branch further from the cell body

Question 8

Irritability

Answer 8

Ability to respond to stimuli

Question 9

Conductivity

Answer 9

Ability to transmit an impulse

Question 10

Neuroglial cells

Answer 10

Provide support and nutrition
Maintain homeostasis
Form myelin
Signal transmission
Support and protection for neurons
Surrounds neurons and holds them in place
Supply nutrients and oxygen to neurons
Insulate neuron
Destroy pathogens and remove dead neurons

Question 11

Schwaan cells

Answer 11

Successive wrapping off the cell membrane form the insulating myelin
Outer surface encased in glycoprotein basement membrane which forms sheath of schwaan

Question 12

Nodes of ranvier

Answer 12

Unmyelinated areas between adjacent schwaan cells
Nerve impulses are generated at these areas

Question 13

Satellite cells

Answer 13

Support neuron cell bodies within ganglia

Question 14

Oligodendrocytes

Answer 14

Provide the insulation(myelin) to neurons in the central nervous system
Each has extensions that form insulating myelin sheaths around several axon

Question 15

Microglia

Answer 15

Phagocytes, migratory

Question 16

Ependymal cells

Answer 16

Line ventricles and secrete CSF

Question 17

Astrocytes

Answer 17

Most abundant glial cells
Star shaped cells that provide physical and nutritional support for neurons
Clean up brain debris
Transport nutrients to neurons
Holds neurons in place
Digest parts of dead neurons
Regulate content of extracellular space

Question 18

Blood brain barrier

Answer 18

Joined by tight junctions
Diffusion active transport endocytosis
Exocytosis

Question 19

How neurons work

Answer 19

Reception
Transmission
Data interpretation
Transmission
Response

Question 20

Reception

Answer 20

Receptors in the skin sense stimuli

Question 21

Transmission

Answer 21

Sensory neurons transmit the touch message

Question 22

Data interpretation

Answer 22

Information is sorted and interpreted

Question 23

Transmission 2

Answer 23

Motor neurons transmit a response message to a muscle

Question 24

Response

Answer 24

Muscles are activated causing a response

Question 25

Impulse transmission

Answer 25

Start with a resting neuron Plasma membrane controls [ ] of ions inside the cell Na+ and K+ on both sides of membrane Na+ higher conc outside K+ higher conc inside

Question 26

How an impulse travels

Answer 26

Stimulus excites neuron Na channels open Na build up inside Inside more + than outside Change in charge (depolarization) Membrane immediately behind depolarization returns to resting state Resting state-inside negative, outside positive

Question 27

Resting state

Answer 27

A neuron is not conducting an impulse The K+ concentration is much higher inside than out Na+ concentration is much higher outside the cell than in

Question 28

Depolarization

Answer 28

A nerve cell is stimulated Membrane becomes permeable to Na for an instant and they quickly move into the cell Inner surface of the cell membrane is now more positively charged then the outside

Question 29

Repolarization

Answer 29

When the membrane becomes depolarized K+ automatically leaves the cell until the cell is back to its resting state