Nervous System

Question 1

Functions of the nervous system:

Answer 1

1. sensory receptors respond to stimuli
2. CNS sums up the input it receives, stores memories, and creates motor responses.
3. generates motor output

Question 2

What does the central nervous system consist of?

Answer 2

brain and spinal cordd

Question 3

What does the peripheral nervous system consist of?

Answer 3

nerves, which lie outside of the CNS

Question 4

Three types of neurons:

Answer 4

sensory neurons, interneurons, motor neurons

Question 5

Function of sensory neuron:

Answer 5

carries nerve signals from a sensory receptor to the CNS

Question 6

Function of Interneuron and where it is found:

Answer 6

found in CNS and receives input from sensory neurons. sums up signals received from neurons and communicates with motor neurons.

Question 7

Motor neuron function:

Answer 7

carries nerve impulses away from CNS to muscle fiber or organ or gland, which carries out the response.

Question 8

Stimulus:

Answer 8

change that activates a neuron

Question 9

Threshold:

Answer 9

minimum voltage that must be reached for action potential to occur. MUST BE MET TO START ACTION POTENTIAL.

Question 10

Depolarization:

Answer 10

when an action potential begins, sodium gates open and Na+ rushes into cell. this causes the inside of axon to become positive.

Question 11

Repolarization:

Answer 11

Na+ gate close and K+ channels open. K+ flows out of cell then the inside of axon becomes negative again. Then, sodium potassium pump completes the action potential. K+ goes back in the cell and resting potential is restored.

Question 12

Sodium potassium pump:

Answer 12

pumps Na+ out and K+ into the neuron. (form of active transport and requires ATP)

Question 13

Saltatory conduction:

Answer 13

in myelinated fibers, action potentials only occur at the nodes of ranvier.

Question 14

Refractory period:

Answer 14

period of time immediately after an action potential during which the axon is unable to conduct another action potential. This ensures the one-way direction of the signal from the cell body down the length of the axon.

Question 15

Synapse:

Answer 15

region of close proximity between two neurons

Question 16

What do the synaptic vessels contain?

Answer 16

neurotransmitters

Question 17

events at a synapse:

Answer 17

1. nerve signals travel along an axon and reach an axon terminal.
2. calcium ions enter the terminal and stimulate synaptic vesicles to merge with the sending membrane.
3. neurotransmitter is released into the synaptic cleft and diffuses across to the receiving membrane.

Question 18

Excitation=

Answer 18

sodium gates to open

Question 19

inhibition+

Answer 19

potassium ions to exit the receiving neuron

Question 20

CNS is wrapped in membranes known as:

Answer 20

meninges

Question 21

Cerebrospinal fluid:

Answer 21

found between the meninges, cushions and protects the CNS. Also in the brain and central canal of spinal cord. drains into cardiovascular system.

Question 22

Gray matter contains:

Answer 22

cell bodies and short, nonmyelinated axons.

Question 23

White matter contains:

Answer 23

myelinated axons that run together in bundles called tracts. myelination occurs and white matter develops as child grows.

Question 24

Structure and contents of the spinal cord:

Answer 24

central canal, gray matter and white matter. spinal nerves project from the cord and through small openings called intervertebral foramina.

Question 25

What kind of disks separate the vertebrae in the spinal cord?

Answer 25

fibrocartilage intervertebral disks.

Question 26

Dorsal root:

Answer 26

sensory fibers entering the gray matter

Question 27

Ventral root:

Answer 27

motor fibers exiting the gray matter

Question 28

Spinal cord functions:

Answer 28

a gateway for pain signals. motor signals from the brain pass down the spinal cord to the muscles. the center of reflex arcs.

Question 29

Paraplegia:

Answer 29

damage in the thoracic region of the spinal cord, lower body and legs are paralyzed.

Question 30

Quadriplegia:

Answer 30

if damage is in the neck region, all four limbs are affected.

Question 31

Reflec arc sets:

Answer 31

1. sensory neurons enter the cord and stimulate many interneurons.
2. nerve signals then travel in these motor fibers to an effector

Question 32

What is the brain made up of?

Answer 32

Cerebrum, diencephalon, cerebellum and brain stem.

Question 33

Frontal lobe helps with:

Answer 33

movement, intelligence, behavior, memory.

Question 34

Temporal lobe helps with:

Answer 34

speech, behavior, hearing, vision.

Question 35

Parietal lobe helps with:

Answer 35

language, sensation, reading.

Question 36

Occipital lobe:

Answer 36

vision

Question 37

Cerebellum helps with:

Answer 37

balance, coordination

Question 38

Brain stem helps with:

Answer 38

breathing, blood pressure, heartbeat, swallowing, consciousness. all the involuntary things.

Question 39

Parts of the brain stem:

Answer 39

midbrain, pons, medulla oblongata.

Question 40

Cerebral cortex is found on:

Answer 40

cerebrum

Question 41

Diencephalon consists of:

Answer 41

Hypothalamus and thalmus

Question 42

what does the hypothalamus do?

Answer 42

regulates hunger, sleep, thirst, body temp, water, balance.

Question 43

What does the thalamus do?

Answer 43

two masses of gray matter which receives all the sensory input except smell. relays to area of cerebrum.

Question 44

Longitudinal fissure:

Answer 44

deep groove that divides the left and right cerebral hemispheres.

Question 45

Thick fold of the cerebrum:

Answer 45

gyri

Question 46

Shallow grooves that separate the gyri:

Answer 46

sulci

Question 47

Which neuron parts receive signals from sensory receptors of other neurons?

Answer 47

dendrites

Question 48

the neuroglia cells that form myelin sheaths in the CNS are called:

Answer 48

Obligodendrocytes

Question 49

repolrization of an axon during an action potential is produced by:

Answer 49

outward diffusion of K+

Question 50

This part of the brain forms the link between the nervous system and the endocrine system:

Answer 50

hypothalamus