introduction to the CNS

Question 1

what is the CNS

Answer 1

the center of all mental activity (thought, learning, memory)

Question 2

____________ and _____________ are responsible for regulating and maintaining homeostasis

Answer 2

CNS; endocrine system

Question 3

CNS components

Answer 3

• the brain
• spinal cord
• nerves
• ganglia

Question 4

sensory receptors

Answer 4

detect internal or external stimuli and relay information to the CNS

Question 5

integration

Answer 5

analysis, storage, decision making, perception

Question 6

motor

Answer 6

• muscular contraction
• glandular secretion

Question 7

CNS v PNS

Answer 7

• CNS: brain and spinal cord
• PNS: nerves and ganglia

Question 8

brain lobes

Answer 8

• frontal
• temporal
• parietal
• occipital
• insular

Question 9

frontal lobe

Answer 9

• decision making
• control of voluntary movement

Question 10

what part of the brain contains Broca’s area

Answer 10

left side of the frontal lobe

Question 11

parietal lobe

Answer 11

processing sensory and spatial information

Question 11

temporal lobe

Answer 11

processing memories and integrating them with emotion and taste, sight, touch, sound

Question 12

what part of the brain contains Wernicke’s area

Answer 12

left side of the temporal lobe

Question 13

occipital lobe

Answer 13

vision

Question 14

does the spinal cord extend the entire length of the vertebral column

Answer 14

no

Question 15

how long is the spinal cord in men and women

Answer 15

• men: 45 cm (18 in)
• women: 43 cm (17 in)

Question 16

spinal cord width in the cervical region

Answer 16

1/2 inch

Question 17

spinal cord width in the lumbar region

Answer 17

1/2 inch

Question 18

spinal cord width in the thoracic region

Answer 18

1/4 inch

Question 19

how many segments in the spinal cord

Answer 19

30

Question 20

spinal cord functions

Answer 20

• conduit of motor information that travels down the spinal cord
• conduit of sensory information in the reverse direction
• center for coordinating certain reflexes

Question 21

embryonic and evolutionary development of the CNS

Answer 21

Question 22

nerve cell parts

Answer 22

• cell body
• dendrites
• axon
• axon terminals

Question 23

nerve cell body

Answer 23

• receptive region
• biosynthesis

Question 24

nerve cell dendrites

Answer 24

- single or multiple - receptive region

Question 25

nerve cell axon

Answer 25

- one per nerve cell - collaterals - sometimes covered in myelin sheath - nodes of ranvier

Question 26

which nerve cells have myelin sheaths

Answer 26

- schwann cells - oligodendrocytes

Question 27

nerve cell axon terminals

Answer 27

- synaptic end bulbs - neurotransmitters

Question 28

white matter v gray matter

Answer 28

Question 29

neuroglia of the CNS (support cells)

Answer 29

- astrocytes - oligodendrocytes - microglia - ependymal cells

Question 30

neuroglia : nerve cell ratio

Answer 30

10:1

Question 31

astrocytes

Answer 31

- physical support - blood-brain barrier - regulation of neurogenesis and synaptogenesis - regulation of chemical environment

Question 32

microglia

Answer 32

phagocytes

Question 33

ependymal cells

Answer 33

produce CSF

Question 34

how do neurons communicate

Answer 34

- action potential - neurotransmitter release - neurotransmitters

Question 35

action potential

Answer 35

- resting potential in neurons is -70 mV - depolarization occurs after action potential is fired - depolarization spreads in one direction

Question 36

what happens when the action potential reaches axon terminals

Answer 36

- action potential reaches the presynaptic axon terminal (neuron 1) - action potential stimulates chemical neurotransmitter from synaptic vesicles - neurotransmitter cross synaptic cleft and reaches postsynaptic neuron (neuron 2) - neurotransmitter binds a receptor - receptor is activated and transmits a signal inside the postsynaptic neuron

Question 37

a chemical synapse is either .... or ...

Answer 37

excitatory; inhibitory

Question 38

excitatory

Answer 38

- triggers influx of Na+ ions - triggers a nerve impulse in the second neuron

Question 39

inhibitory

Answer 39

- increases membrane permeability to K+ or Cl- ions - inhibits action potential in the second neuron

Question 40

agonists

Answer 40

stimulate the receptor

Question 41

antagonists

Answer 41

inhibit the receptor by blocking the neurotransmitter action

Question 42

action of neurotransmitters is carefully regulated by __________, _________, or _______________

Answer 42

diffusion; reuptake; degradation

Question 43

neuromuscular junction

Answer 43

- specialized synapse between a motor neuron and a muscle fiber - occurs mid-length of muscle fiber

Question 44

neuromuscular junction neurotransmitter

Answer 44

acetylcholine

Question 45

where is the acetylcholine receptor in a neuromuscular junction

Answer 45

motor end of the muscle fiber

Question 46

what does the binding of acetylcholine to its receptor trigger

Answer 46

influx of Na+ ions and generation of a muscle action potential