Unit III: The Nervous System

Question 1

Sensory Input

Answer 1

PNS
Conveys information about the conditions inside or outside of the body.
Carry information to the CNS

Question 2

Integration

Answer 2

CNS
Processes sensory information
“Important or not?”

Question 3

Motor Output

Answer 3

PNS
Controls or adjusts peripheral organs such as skeletal muscles.

Question 4

What does the central nervous system consist of?

Answer 4

Brain and the spinal cord.

Question 5

What does the peripheral nervous system consist of?

Answer 5

Includes all the nervous tissue outside of the CNS

Question 6

Sensory (afferent)

Answer 6

PNS brings sensory information to the CNS from receptors in peripheral tissues or organs.

Question 7

Motor (efferent)

Answer 7

PNS carries motor commands from the CNS to muscles, glands, and adipose tissue.

Question 8

Effectors

Answer 8

Targeted organs that respond by doing something.

Question 9

What are the two divisions of the motor (efferent) division?

Answer 9

Somatic Nervous System and Automatic Nervous System.

Question 10

Somatic Nervous System (SNS)

Answer 10

Controls the skeletal muscle contractions.
Voluntary contractions and involuntary contractions.

Question 11

Autonomic Nervous System (ANS)

Answer 11

The visceral motor system automatically regulates smooth, cardiac muscles and glandular secretions, and adipose tissue at a subconscious level.

Question 12

Which subdivision of the automatic nervous system is active during stress?

Answer 12

Sympathetic
* its role is to respond to dangerous and stressful situations.
*“Fight or Flight”
Increases heart rate and respirations.

Question 13

What subdivision of the automatic nervous system is most active at rest?

Answer 13

Parasympathetic
* Responsible for the body’s rest and digestion response when the body is relaxed, resting, or feeding.
*undoes the work of sympathetic divisions in stressful situations.
*Decreases the respiration rate and the heart rate.

Question 14

Neuroglia

Answer 14

It supports cells in nervous tissue, separates and protects the neurons, and helps regulate the composition of the interstitial fluid.

Question 15

Which types of neuroglia are found in the CNS?

Answer 15

Astrocytes
Microglia-Phagocytes
Ependymal
Oligodendrocytes

Question 16

What types of neuroglia are found in the PNS?

Answer 16

Satellite and Schwann

Question 17

Astrocytes

Answer 17

*Brace neurons
*Maintains Blood-Brain Brain (between capillaries and neurons to protect brain)
*Forms scar tissue after injury.

Question 18

Microglia-Phagocytes

Answer 18

Removes cell debris, wastes, and pathogens by phagocytes.

Question 19

Ependymal

Answer 19

Makes cerebrospinal fluid line the ventricles of the brain and central canal. Assist with circulating and monitoring the CSF.

Question 20

Oligodendrocytes

Answer 20

Myelinated CNS axons provide a structural framework.

Question 21

Satellite Cells

Answer 21

*Protect neuron cell bodies.
*Surround neuron cell bodies in ganglia.
*Regulates oxygen, carbon dioxide, nutrients, and neurotransmitter levels.

Question 22

Dendrites

Answer 22

Sensitive processes (extensions) that extend and branch out from the cell body.
Role in intercellular communication.
CNS neurons receive information from other neurons here.

Question 23

Perikaryon

Answer 23

Cytoplasm surrounding the nucleus.

Question 24

Telodendria

Answer 24

Fine extensions at the end of the main axon trunk and collaterals.
End at axon terminals, which play a role in communication with another cell.

Question 25

Axon

Answer 25

Long cytoplasmic process, which is capable of propagating an electrical impulse known as an action potential.

Question 26

Nissl Substance

Answer 26

Granular clusters of Rough ER and ribosomes are found within the cell body of organs. *They give a gray color to areas containing neuron cell bodies

Question 27

Axon Terminal

Answer 27

Play a role in communication with other another cell. Releases neurotransmitters and conducts electrical impulses.

Question 28

Neurofibrils

Answer 28

Neurofilaments and neurotubules in the cytoplasm of the neuron. Cytoskeleton. **Structural support**

Question 29

Myelin

Answer 29

Membranous wrapping serves as electrical insulation and increases the speed at which an action potential travels along the axon.

Question 30

Myelin Sheath

Answer 30

Fat that coats around most axons in the PNS.

Question 31

What is the function of myelin?

Answer 31

Protects, insulates, and increases the speed of the action potential.

Question 32

Structure of Schwann Cells

Answer 32

*Jelly roll-like fashion. *Neurilemma on the outer surface of the axon that encircles an axon. *The nodes of Ranvier are not very far apart from adjacent internodes.

Question 33

Nodes of Ranvier

Answer 33

Gaps in the myelin sheath that cover the axon of a neuron

Question 34

Structure of Oligodendrocytes

Answer 34

*Contain myelin *Nodes of ranvier are far apart. *No neurilemma

Question 35

What is the difference between white matter and gray matter?

Answer 35

White Matter- myelin is present. Gray Matter- contains the neuron body only. No myelin is present.

Question 36

Multipolar Neurons

Answer 36

*Most common in CNS *Motor and association neurons. *Has more than two processes *Single axon and multiple dendrites.

Question 37

Unipolar Neurons

Answer 37

*Most **sensory neurons** in the PNS. *Single, elongated process. *The cell body is located on the side.

Question 37

Bipolar Neurons

Answer 37

*Rare *Sensory organs like ear, eye, and nose. *The cell body separates two processes.

Question 38

Proprioceptors

Answer 38

Monitor the position and movement of skeletal muscles and joint.

Question 39

Exteroceptor (Sensory)

Answer 39

Provide information about the external environment in the form of touch, temperature, or pressure sensations and the more complex senses or taste, smell, sight, equilibrium, and hearing.

Question 40

Interceptors

Answer 40

Monitors the digestive, respiratory, cardiovascular, urinary, and reproductive systems and provides sensations of distension, deep pressure, and pain.

Question 41

What is the structural classification of motor neurons?

Answer 41

Multipolar neurons

Question 42

What are the structural classification of sensory (afferent) neurons?

Answer 42

Bipolar and unipolar

Question 43

Neurotransmitter

Answer 43

Chemical messengers that allow neurons to communicate with muscles and glands

Question 44

Dendrites receive ___________ signals which are converted to an ___________ signal.

Answer 44

Chemical Electrical

Question 45

what types of nerves release acetylcholine?

Answer 45

Somatic motor neurons and some ANS neurons.

Question 46

What types of nerves release norepinephrine?

Answer 46

Some neurons of the sympathetic branch of the ANS Related to epinephrine (made by the adrenal glands) and dopamine

Question 47

Excitatory Neurotransmitter- Stimulatory Effect

Answer 47

Depolarization and Action potentials

Question 48

Inhibitory Neurotransmitters

Answer 48

Membrane potential drops below -70mV (the normal resting membrane potential of a neuron) HYPERPOLARIZATION

Question 49

Depolarization

Answer 49

When the cell membrane becomes less negative

Question 50

Hyper polarization

Answer 50

When the membrane potential drops below -70mV (the normal resting membrane potential.

Question 51

Is NE stimulatory or inhibitory?

Answer 51

Excitatory, smooth muscles, cardiac and glands.

Question 52

Is ACh stimulatory (excitatory) or inhibitory?

Answer 52

ACh is both. Skeletal muscles - E Cardiac muscles - I Digestive tract and smooth muscles- E