The Nervous System Chp33

Question 1

What is the CNS

Answer 1

Central Nervous System (brain and spinal cord)

Question 2

What is the PNS

Answer 2

Peripheral Nervous System (rest of the body/not brain or spinal cord)

Question 3

What is a neuron

Answer 3

a nerve cell

Question 4

What is a sensory neuron

Answer 4

takes a message from a sense organ to the CNS

Question 5

What is a motor nueron

Answer 5

takes a message from the CNS to a muscle or a gland

Question 6

What are the parts of a neuron

Answer 6

neurotransmitter swellings, axon, cell body, node of Ranvier, Schwann cell, myelin, dendrite

Question 7

What is the function of a receptor

Answer 7

detects a stimulus

Question 8

What is the function of nerve endings

Answer 8

connect sensory neurons to receptor cells or sense organs

Question 9

What is the function of dendrites

Answer 9

carry impulses toward the cell body

Question 10

What is the function of axons

Answer 10

carry impulses away from cell bodies

Question 11

What is the function of Schwann cells

Answer 11

produce the myelin sheath

Question 12

What is the function of myelin sheaths

Answer 12

insulates the electrical impulses

Question 13

What is the function of the cell body

Answer 13

produces neurotransmitter chemicals

Question 14

What is the function of neurotransmitter swellings

Answer 14

release chemicals that carry the impulse from one nerve cell to another

Question 15

What is a ganglion

Answer 15

a group of cell bodies located outside the CNS

Question 16

What is an interneuron

Answer 16

carries information between sensory and motor neurons

Question 17

What is the threshold

Answer 17

the minimum stimulus needed to cause an impulse to be carried in a neuron

Question 18

What is the all or nothing law

Answer 18

states that if the threshold is reached an impulse is carried, but if the threshold is not reached no impulse is carried

Question 19

What is the refractory period

Answer 19

a short time span after a neuron has carried and impulse during which a stimulus fails to cause a response

Question 20

What affects the speed of an impulse

Answer 20

myelin sheath, diameter of axon or dendrite (larger is faster)

Question 21

What is a synapse

Answer 21

a region where two neurons come into close contact

Question 22

What is a synaptic cleft

Answer 22

the tiny gap between the two neurons at the synapse

Question 23

Describe the passage of an impulse across a synapse

Answer 23

the impulse stimulates neurotransmitter swellings in the pre-synaptic neuron to release neurotransmitters that diffuse across the cleft, then it combines with receptors and is broken down while the impulse is sent

Question 24

What are the functions of the synapse

Answer 24

transmit impulses, control the direction of the impulse

Question 25

What are the parts of the brain

Answer 25

cerebrum (forebrain), cerebellum (hindbrain), medulla oblongata, thalamus, hypothalamus, pituitary gland

Question 26

What is the function of the cerebrum

Answer 26

controls voluntary movements

Question 27

What is the function of the cerebellum

Answer 27

balance and coordination

Question 28

What is the function of the medulla oblongata

Answer 28

controls involuntary movements (breathing, coughing)

Question 29

What is the function of the thalamus

Answer 29

the sorting centre of the brain

Question 30

What is the function of the hypothalamus

Answer 30

homeostasis

Question 31

What is the function of the pituitary gland

Answer 31

produces hormones

Question 32

What is a nervous system disorder

Answer 32

Parkinson's disease

Question 33

What is the cause for Parkinson's disease

Answer 33

when the brain doesn't produce enough dopamine

Question 34

What is a treatment for Parkinson's disease

Answer 34

physiotherapy, L-dopa

Question 35

What are the parts of the spinal cord

Answer 35

white matter, grey matter, central canal, dorsal root swelling, dorsal root, ventral root, sensory/motor/interneuron

Question 36

What is a reflex action

Answer 36

an automatic, involuntary, unthinking response to a stimulus

Question 37

What are the advantages of reflex action

Answer 37

protects the body from damaging stimulus

Question 38

What is a reflex arc

Answer 38

the pathway taken by a nerve impulse in a reflex action