organization of the human nervous system

Question 1

what are the three types of nerve cells in the nervous system?

Answer 1

1. sensory (afferent)
2. motor (efferent)
3. interneurons

Question 2

______________ neurons transmit sensory information to the spinal cord and brain

Answer 2

sensory

Question 3

__________ neurons trasmit motor information from the brain and spinal cord to muscles and glands

Answer 3

motor

Question 4

___________ are found between other neurons and are he most numerous of the three types

Answer 4

interneurons

Question 5

where are interneurons predominantly found?

Answer 5

brain and spinal cord

Question 6

T / F - motor neurons are often linked to reflexive behavior

Answer 6

false, interneurons = reflexive

Question 7

reflexes only require processing at the level of the ____________

Answer 7

spinal cord

Question 8

____________ circuits are used when certain actions require input from the brain or brainstem

Answer 8

supraspinal

Question 9

two large divisions of the nervous system

Answer 9

1. CNS
2. PNS

Question 10

what is the CNS composed of?

Answer 10

brain
spinal cord

Question 11

__________ matter consists of axons encased in myelin sheaths

Answer 11

white matter

*white people need protection

Question 12

____________ matter consists of unmyelinated cell bodies and dendrites

Answer 12

grey matter

Question 13

in the brain, ________ matter lies deeper than _________ matter

Answer 13

white matter lies deeper than grey matter

Question 14

what are the four regions of the spinal cord?

Answer 14

1. cervical
2. thoracic
3. lumbar
4. sacral

Question 15

the spinal cord is protected by the ____________

Answer 15

vertebral column

Question 16

in the spinal cord, ________ matter lies deeper than _________ matter

Answer 16

grey matter lies deeper than white matter

Question 17

the cell bodies of the sensory neurons of the spinal cord are found in the (ventral / dorsal) root ganglia

Answer 17

dorsal

Question 18

the cell bodies of the motor neurons exit the spinal cord on the (ventral / dorsal) side

Answer 18

ventral

Question 19

what is the PNS composed of?

Answer 19

spinal nerves
cranial nerves

Question 20

what are the two subdivisions of the PNS?

Answer 20

1. autonomic
2. somatic

Question 21

what does the autonomic nervous system control?

Answer 21

involuntary muscles
- heartbeat
- respiration
- digestion
- gland secretions
- temperature control

Question 22

what does the somatic nervous system control?

Answer 22

voluntary muscles
sensory / motor neurons throughout the skin, joints, and muscleswha

Question 23

what is one primary differnce between the autonomic and somatic nervous system (besides what they control)?

Answer 23

ANS contain two neurons, while the SNS only contains one

Question 24

a motor neuron in the SNS goes from __________ and ___________

Answer 24

spinal cord to muscle

*no synapse is needed

Question 25

what are the names of the two neurons in the ANS that work in series to trasmit messages from the spinal cord?

Answer 25

1. preganglionic neuron 2. postganglionic neuron

Question 26

where is the preganglionic neuron located? postganglionic neuron?

Answer 26

preganglionic neuron = CNS postganglionic neuron = PNS

Question 27

what are the two subdivisions of the ANS?

Answer 27

1. parasympathetic 2. sympathetic

Question 28

what does the sympathetic nervous system control?

Answer 28

fight or flight - incrased heart rate - pupil dilation - digestion inhibition - redistributes blood to muscles - increase blood glucose - relaxes bronchi

Question 29

what does the parasympathetic nervous system control?

Answer 29

rest and digest - increased peristalsis - conserve energy - reduce heart rate - constrict brochi - increased exocrine secretion - epinephrine release

Question 30

_____________ is the neurotransmitter responsible for parasympathetic responses in the body

Answer 30

acetylcholine

Question 31

_____________ is released by the preganglionic neurons, ____________ is released by the postganglionic neurons of the sympathetic nervous system

Answer 31

preganglionic = acetylcholine postganglionic = norepinephrine

Question 32

neural circuits called ___________ control reflexive bahviors

Answer 32

reflex arcs

Question 33

what are the two types of reflex arcs

Answer 33

1. monosynaptic 2. polysynaptic

Question 34

_______________ reflex arc is a single synapse between the sensory neuron that receives the stimulus and the motor neuron that responds to it

Answer 34

monosynaptic

Question 35

what is an examples of a reflex that utilizes a monosynaptic reflex arc?

Answer 35

knee jerk reflex

Question 36

____________ reflex arc is at least one interneuron between the sensory and motor neurons

Answer 36

polysynaptic

Question 37

what is an examples of a reflex that utilizes a polysynaptic reflex arc?

Answer 37

withdrawal reflex *step on a nail, pull back