PRACTICE QUIZ UNIT 9

Question 1

Dendrite

Answer 1

Receives input from other neurons

Question 2

Cell body

Answer 2

Part of neuron with most cytoplasm

Question 3

Cause of white appearance on white matter

Answer 3

Presence of myelin

Question 4

Cervical, lumbar, sacral, coccygeal, thoracic: which is not part of a spinal cord

Answer 4

Coccygeal

Question 5

What are groups of cell bodies in PNS called

Answer 5

Ganglia

Question 6

Cerebrum function

Answer 6

Memory, emotion, consciousness

Question 7

Diencephalon function

Answer 7

Regulate homeostasis

Question 8

Midbrain of brain stem function

Answer 8

Visual space, auditory space, somatosensory space

Question 9

Hindbrain of brain stem function

Answer 9

Heart contraction and rate of breathing

Question 10

Cerebellum function

Answer 10

Coordination and motor activity precision

Question 11

Order of brain meninges and structures from deepest to superficial

Answer 11

Cerebral cortex -> pia mater -> arachonoid trabeculae -> arachnoid mater -> subdural space -> dura mater -> cranial bone

Question 12

What stimulus opens the ligand gated

Answer 12

Neurotransmitter

Question 13

What stimulus opens the leakage

Answer 13

No specific event

Question 14

What stimulus opens mechanically gated

Answer 14

Pressure or touch

Question 15

What stimulus opens voltage gated

Answer 15

Action potential

Question 16

What is myelin, what cells produce it and why is it important in nervous system function

Answer 16

• Myelin is a lipid rich sheath surrounding axon
• Produced by oligodendrocytes in CNS and schwann cells in PNS
• Important for facilitating transmission of electrical signals across axon

Question 17

Relative to PNS, what’s the difference between nerve and ganglion

Answer 17

• Nerve is the term for a bundle of axons (white matter)
• Ganglion is a term for a group of neuron cell bodies (Gray matter)

Question 18

Steps involved in proves of generalized reflex arc

Answer 18

• Sensory neuron triggered and sends nerve impulse to spinal cord
• Motor neuron stimulated to send nerve impulse to skeletal muscle
• Voluntary skeletal muscle reaction occurs as a response to sensory input

Question 19

3 factors contributing to resting membrane potential of neuron

Answer 19

• Sodium ions concentrated outside cell
• Potassium ion concentrated inside cell
• Cytosol contains many anions and negatively charged proteins

Question 20

Resting potential

Answer 20

The sodium/potassium pump maintains potential; sodium and potassium channels are closed

Question 21

Depolarization

Answer 21

Sodium ion channels open and sodium ions diffuse into neuron; potassium channels closed

Question 22

Repolarization

Answer 22

Potassium channels open and potassium ions diffuse out of neuron; sodium channels closed

Question 23

Hyperpolarization

Answer 23

Potassium channels stay open below resting membrane potential; slight delay in closing; sodium channels closed

Question 24

Describe the events occurring after an action potential reaches axon terminal that leads to stimulation of another neuron (7)

Answer 24

• Action potential reaches axon terminal
• Voltage gated Ca2+ channels in membrane of synaptic end bulb opens
• Ca2+ ions facilitate the merging of synaptic vesicles with presynaptic membrane
• NT released through exocytosis into synaptic cleft
• NT diffuses to postsynaptic membrane interacting with NT receptors
• Result in depolarization or hyperpolarization leading to excitation or inhibition
• NT removed from synaptic cleft by diffusion or from action of enzymes that break it down chemically or by transporters in presynaptic cell membrane

Question 25

Roles of activation and inactivation gates in resting neuron and during action potential (4)

Answer 25

- Activation gates closed and inactivation gates open during resting potential - Once threshold is reached, activation gates open and sodium diffuses into neuron - At peak depolarization, inactivation gates close and sodium ions dont diffuse - When the potential passes threshold again, inactivation gates open and activation gates close; sodium ions dont diffuse

Question 26

Difference between the 2 anatomical divisions of nervous system

Answer 26

- CNS: Composed of brain and spinal cord - PNS: Everything outside of CNS

Question 27

Difference between tract and nerve

Answer 27

- Tract: Bundle of axons (white matter) in CNS - Nerve: Bundle of axons (white matter) in PNS

Question 28

3 basic process involved in functioning of nervous system

Answer 28

- Sensation: senses register presence of an event in environment - Integration: Senses communicate presence of stimulus through system where that information is proceeded; combining higher cognitive functions such as learning, memory and emotion - Response: Contraction of skeletal muscle (voluntary) or contraction of smooth muscle, regulation of cardiac muscle, activation of glands (involuntary)

Question 29

Difference between somatic and autonomic divisions in nervous system

Answer 29

- SNS: Controls conscious perception and voluntary motor responses - ANS: Responsible for involuntary control of the organ system of body

Question 30

Dendrite function

Answer 30

Receive information from other neurons

Question 31

Cell membrane function

Answer 31

Separates cytoplasm from extracellular environment and regulates passage in and out cell

Question 32

Cell body function

Answer 32

Main part of neuron containing nucleus and most of major organelles

Question 33

Axon function

Answer 33

Fiber emerging from cell body and projects to target cells

Question 34

Oligodendrocyte function

Answer 34

Glial cell that produces myelin in CNS

Question 35

Myelin function

Answer 35

Layers or insulating lipids surrounding portions of axons

Question 36

Nodes of ranvier function

Answer 36

Periodic gaps in myelin