Chapter 2

Question 1

What is the only substrate that can be used by the nervous system?

Answer 1

glucose

-low blood glucose = hypoglycemia, symptoms of depressed nervous system

Question 2

What is the purpose of the nervous system?

Answer 2

primary control, regulation, and communication

Question 3

What are the 3 basic functions of the nervous system?

Answer 3

1. Sensory- monitors change internally and externally
2. Process- interprets sensory input and coordinates response
3. Motor- excites and inhibits effector organs

Question 4

Effector organs?

Answer 4

• target organs
• stimulated or inhibited by the motor neurons of the nervous system or by hormones released by endocrine glands
• include all visceral organs and skeletal muscle

Question 5

Neuron?

Answer 5

basic structure of the nervous system, one nerve cell

Question 6

T/F

All neurons are unidirectional.

Answer 6

true

Question 7

Nerve impulses are transmitted as _____ ______.

Answer 7

action potentials

Question 8

Synapse?

Answer 8

the junction between two neurons

Question 9

What happens when a neuron depolarizes?

Answer 9

it releases neurotransmitters, which bind to a matching receptor causing an EPSP or IPSP

Question 10

Sensory (afferent) neurons?

Answer 10

transmit impulses from receptor to CNS

Question 11

Motor (efferent) neurons?

Answer 11

transmit impulses from CNS to effector organs

Question 12

Interneurons?

Answer 12

connect sensory and motor neurons within the CNS

Question 13

Besides bone, what protects the brain and spinal cord?

Answer 13

meninges and CSF

Question 14

Why does the outer portion of the cerebral cortex appear gray?

Answer 14

• lack of myelin sheath

- contains cell bodies

Question 15

Function of cerebellum?

Answer 15

produce smooth and coordinated movements

Question 16

What composes the Diencephalon?

Answer 16

Thalamus and Hypothalamus

Question 17

Thalamus function?

Answer 17

• sensory integration center

- receives sensory info and relays it to appropriate portion of cerebrum

Question 18

Hypothalamus function?

Answer 18

maintain homeostasis through control of autonomic control centers, emotional response, body temp, food intake, water balance, thirst, sleep cycles, endocrine function

Question 19

What composes the brain stem?

Answer 19

midbrain
pons
medulla

Question 20

brain stem function?

Answer 20

relay info between brain and spinal cord

Question 21

pons function?

Answer 21

bridge from brain to spinal cord, helps control respiration

Question 22

medulla function?

Answer 22

• control centers for cardiovascular and respiratory systems
• force and rate of contraction of cardiac muscle
• vasoconstriction and dilation of blood vessels to regulate blood pressure

Question 23

Nerves?

Answer 23

axons of many sensory or motor neurons arranged in bundles (fascicles) encased in layers of connective tissue, blood vessels in between fascicles

Question 24

How many pairs of spinal nerves?

Answer 24

31

Question 25

How many pairs of cranial nerves?

Answer 25

12 -they supply special senses and skeletal muscles of head and neck

Question 26

Ganglia?

Answer 26

clusters of neuron cell bodies

Question 27

Where are sensory neuron cell bodies located?

Answer 27

Dorsal Root Ganglia

Question 28

Where are motor neuron cell bodies located?

Answer 28

sympathetic chain ganglia and collateral ganglia

Question 29

What is the function of ganglia?

Answer 29

allows a single neuron to enter and synapse with many other neurons, increases efficiency

Question 30

Sensory info comes from what two general areas?

Answer 30

1. visceral sensory nervous system- visceral effector organs, smooth muscle, special senses, blood and lymph vessels, cardiac muscle, glands 2. somatic sensory- skin, skeletal muscle, muscle, joints

Question 31

mechanoreceptors?

Answer 31

detect movement, stretch, tension, pressure, and touch -pacinian- rapid adapting, rufinnis- slow adapting

Question 32

Chemoreceptors?

Answer 32

detect changes in O2, CO2, glucose, pH, electrolytes

Question 33

Thermoreceptors?

Answer 33

detect changes in temp

Question 34

What are the two main divisions of the motor PNS?

Answer 34

1. autonomic | 2. somatic

Question 35

What does the autonomic nervous system control?

Answer 35

smooth muscle, cardiac muscle, glands, visceral organs

Question 36

What are the 2 subdivisions of the autonomic nervous system?

Answer 36

1. sympathetic | 2. parasympathetic

Question 37

T/F | Autonomic control is involuntary.

Answer 37

True

Question 38

Dual Innervation?

Answer 38

organs are innervated by both sympathetic and parasympathetic

Question 39

Antagonistic control?

Answer 39

dual innervation that have opposite effects, activity of organ is related to the net effect of the stimulation, more dominant response wins

Question 40

Sympathetic is considered _____ and parasympathetic is _____.

Answer 40

- fight or flight, excitatory | - rest and digest, inhibitory

Question 41

What is the advantage of antagonistic control?

Answer 41

provides precise control of the organ (ex. heart rate)

Question 42

What is the initial increase in heart rate during exercise due to? further increases?

Answer 42

- initial- withdrawal of parasympathetic | - further- increase in sympathetic

Question 43

What effector organs do not have dual innervation by the autonomic system? what type of control is this?

Answer 43

- smooth muscle in blood vessels, only sympathetic | - Tonic control- only controlled by one system

Question 44

How can sympathetic stimulation cause two different responses at two different locations?

Answer 44

depends on the neurotransmitter that is released and the receptor it binds

Question 45

Function of somatic motor nervous system?

Answer 45

- Excitatory impulses from spinal cord to skeletal muscle - voluntary - reflexes

Question 46

Does the somatic system have dual innervation?

Answer 46

no, only single innervation which is always excitatory

Question 47

Contraction?

Answer 47

development of tension

Question 48

Contraction of skeletal muscle results in what?

Answer 48

stabilization or mobilization of the joint

Question 49

Where does inhibition of skeletal muscle take place?

Answer 49

CNS