Nervous

Question 1

Neurons examples:

Answer 1

*Cell body
* Dendrites
* Axon
*Myelin sheath
* Nodes of Ranvier
—gaps between
myelin sheath on the axon fiber

Question 2

*Cell body

Answer 2

contains nucleus and other
organelles

Question 3

Dendrites

Answer 3

fan out to receive signals
from sensory receptors or other
neurons

Question 4

Axon

Answer 4

fibers longer than dendrites,
conducts impulses away from cell body

Question 5

Myelin sheath

Answer 5

formed from
membranes of tightly spiraled cells,
helps impulses travel faster on long
axons, makes nerves look white

Question 6

Nodes of Ranvier

Answer 6

gaps between
myelin sheath on the axon fiber

Question 7

The nerve impulse is dependent on ____ _____

Answer 7

concentration gradients

Question 8

concentration gradients are maintained by ___-____ _____

Answer 8

sodium-potassium pump

Question 9

sodium-potassium pump

Answer 9

Actively transports sodium ions (Na+) outside axon and
actively transports potassium ions (K+) inside
* This creates: the charge difference!

Question 10

• Charge difference

Answer 10

inside of axon negative compared to
outside
* Due to unequal distribution of sodium and potassium
cause the inside to have an overall – charge where the
outside has an overall positive charge.

Question 11

Action potential

Answer 11

or a nerve impulse uses this charge
difference to trigger quick responses throughout the body

Question 12

Communication between cells

Answer 12

Dendrites receive the signal –> Signal travels to cell body
and is integrated –> Axons carry the signal out of cell body
–> Signal travels down axon to axon terminal where
neurotransmitters are released across synapse to
dendrites of another neural cell

Question 13

Synapse

Answer 13

region where axon meets its target cell

Question 14

Neurotransmitters

Answer 14

chemical messages allowing neurons
to communicate

Question 15

Presynaptic cell

Answer 15

transmits the signal carrying the
message

Question 16

Postsynaptic cell

Answer 16

– receives signal from presynaptic cell

Question 17

Synaptic cleft

Answer 17

space between pre and postsynaptic cell

Question 18

Nervous system is divided into two parts:

Answer 18

central nervous system (CNS) and
peripheral nervous system (PNS)

Question 19

central nervous system (CNS)

Answer 19

brain and spinal cord
* White and gray matter organization
* Cerebrum and spinal cord structure

Question 20

peripheral nervous system (PNS)

Answer 20

autonomic and somatic divisions

Question 21

peripheral nervous system (PNS) – autonomic

Answer 21

controls smooth & cardiac muscles, glands, functions
“automatically”

Question 22

PNS somatic divisions

Answer 22

• Controls voluntary motor movements of skeletal muscles

Question 23

PNS autonomic –> Sympathetic

Answer 23

Activates the fight-or-flight response. Works reciprocally with the
parasympathetic system to maintain homeostasis

Question 24

PNS autonomic –> Parasympathetic

Answer 24

devoted to resting and digesting

Question 25

The Cerebrum (Telencephalon) is the most developed area of the brain and is responsible for ______

Answer 25

higher mental capabilities.

Question 26

Frontal Lobe

Answer 26

controls motor functions and permits voluntary muscle control; is responsible for abilities to think, problem solve, speak, and smell

Question 27

Parietal lobe

Answer 27

receives information from sensory receptor located in the skin and the taste receptors in the mouth (somatosensory cortex)

Question 28

Occipital Lobe

Answer 28

Interprets visual input and combines visual images with other sensory experiences. The optic nerves split.

Question 29

Temporal lobe

Answer 29

has sensory areas for hearing and smelling. Processes auditory information and language comprehension

Question 30

Ventricles:

Answer 30

The interconnecting spaces that produce and serve as a reservoir for cerebrospinal fluid, which cushions the brain

Question 31

Cerebrum

Answer 31

Communicates with, and coordinates the activities of, the other parts of the brain.

Question 32

Two halves (hemispheres), each half has a number of lobes * Most of the ____ is white matter (long axons of interneurons taking impulses to and from _____)

Answer 32

cerebrum

Question 33

Cerebral cortex

Answer 33

* Ensures coordinated, smooth, voluntary movements highly convoluted outer layer of gray matter covering the cerebrum * Contains over a billion cell bodies * Region that interprets and initiates sensation, voluntary movement, and higher thought processes

Question 34

Diencephalon is composed of:

Answer 34

Thalamus and Hypothalamus

Question 35

Thalamus

Answer 35

* Receiving end for all sensory input except smell * Integrates information and sends it to appropriate place in cerebrum

Question 36

Hypothalamus

Answer 36

* Integrating center that helps maintain homeostasis by regulating sleep, hunger, thirst, body temperature, and water balance

Question 37

Brain stem contains ___, ___,____

Answer 37

midbrain, pons, and medulla oblongata

Question 38

The brain stem connects _____

Answer 38

* Connects rest of the brain to spinal cord Contains tracts that ascend or descend between spinal cord and higher brain centers

Question 39

Midbrain contains

Answer 39

important visual and auditory reflex centers

Question 40

Pons links ___ with ____, sleep and dreaming

Answer 40

medulla with midbrain

Question 41

Medulla oblongata contains reflex centers for

Answer 41

regulating heartbeat, breathing, and vasoconstriction

Question 42

Reflexes are triggered by a ____ and result in a ____ response.

Answer 42

stimulus, predictable

Question 43

Reflexes are ___ and ___

Answer 43

fast and invlountary

Question 44

Reflexes have four to five main components.

Answer 44

1.Receptor 2. Afferent (sensory) neuron 3. Efferent (motor) neuron 4. Effector

Question 45

Receptor

Answer 45

A receptor detects the appropriate stimulus. pain receptors in the skin

Question 46

Afferent (sensory) neuron

Answer 46

The sensory neuron conducts the signal from the receptor to the spinal cord.

Question 47

Afferent (sensory) neuron --> Interneuron

Answer 47

maybe located within the spinal cord to receive the signal from the sensory neuron. The presence of an interneuron indicates a polysynaptic reflex (aka the signal entering the interneuron triggers several responses – reaction to burning is a good example/ all your hand and arm muscles respond).

Question 48

Efferent (motor) neuron:

Answer 48

The motor neuron receives a signal from either the sensory or interneuron and carries the signal to the effector. * If the signal passes directly from the sensory neuron to the motor neuron, it is a monosynaptic reflex (aka a single motor response - knee jerk reaction is a good example).

Question 49

Effector

Answer 49

muscle response, The effector (what gets acted on) executes the response of the reflex. In the spinal reflexes tested in this activity, the effectors are skeletal muscles (biceps, triceps, etc).

Question 50

Several different monosynaptic reflexes:

Answer 50

biceps brachii reflex triceps brachii reflex patellar reflex calcaneal reflex plantar reflex