Nervous System

Question 1

Neurons

Answer 1

Cell of the nervous system specialized to generate and transmit electrical signals (action potentials and graded potentials).

Question 2

Dendrites

Answer 2

Branching neuron process that serves as a receptive, or input, region; transmits an electrical signal toward the cell body.

Question 3

Axons

Answer 3

Neuron process process that carries action potentials away from the nerve cell body; efferent process; the conducting portion of a nerve cell.

Question 4

Schwann Cells

Answer 4

A type of supporting cell in the PNS; forms myelin sheaths and is vital to peripheral nerve fiber regeneration. Also called a neurolemmocyte.

Question 5

Myelin

Answer 5

Fatty insulating sheath that surrounds all but the smallest nerve fibers.

Question 6

Neurilemma

Answer 6

The thin sheath that surrounds all but the smallest nerve fibers.

Question 7

Nodes of Ranvier

Answer 7

A gap in the sheath of a nerve, between adjacent Schwann cells.

Question 8

Synapse

Answer 8

Functional junction or point of close contact between two neurons or between a neuron and an effector cell.

Question 9

Nissl Bodies

Answer 9

A large granular body found in neurons, believed to be primarily concerned with the synthesis of proteins for intercellular use.

Question 10

Neuroglia

Answer 10

Nonexcitable cells of neural tissue that support, protect, and insulate the neurons; glial cells.

Question 11

Astrocytes

Answer 11

A type of CNS supporting cell; assists in exchanges between blood capillaries and neurons.

Question 12

Oligodendrocytes

Answer 12

A type of CNS supporting cell that composes myelin sheaths.

Question 13

Microglia

Answer 13

A type of CNS supporting cell; can transform into phagocytes in areas of neural damage or inflammation.

Question 14

Autonomic Nervous System

Answer 14

Part of the nervous system that controls the visera, such as the heart and various glands, and thus causes involuntary sub-conscious actions.

Question 15

Sympathetic Nervous System

Answer 15

Part of the nervous system that controls the peripheral nervous system that lead to the skeletal muscles, and thus causes voluntary actions.

Question 16

Central Nervous System

Answer 16

The complex of nerve tissue that controls the activities of the body, and comprises the brain and spinal cord.

Question 17

Peripheral Nervous System

Answer 17

Parts of the nervous system that relays nerve impulses to and from the brain and spinal cord; and comprises cranial nerves and spinal nerves.

Question 18

Sensory Neuron

Answer 18

An afferent nerve cell that detects and responds to external signals.

Question 19

Motor Neuron

Answer 19

An efferent nerve cell responsible for carrying signals away from the CNS towards the muscles to cause movement.

Question 20

Interneuron

Answer 20

Nerve cell located between motor and sensory neurons that shuttles signals through CNS pathways where integration occurs.

Question 21

Resting Potential of Nerve

Answer 21

The imbalance of electrical charge that exists between the interior of electrically excitable neurons (nerve cells) and their surroundings.

Question 22

Action Potential of Nerve

Answer 22

A large transient depolarization event, including polarity reversal, that is propagated along the membrane of a muscle cell or an axon of a neuron.

Question 23

Excitatory Postsynaptic Potential

Answer 23

When a neurotransmitter can depolarize the postsynaptic membrane; triggering an action potential for the neuron.

Question 24

Inhibitory Postsynaptic Potential

Answer 24

When a neurotransmitter binds with other receptors and increases membrane permeability to potassium ions, which hyperpolarize the postsynaptic membrane; prevents an action potential foe the neuron.

Question 25

Refractory Period

Answer 25

A period of time during which a cell is incapable of repeating an action potential.

Question 26

Acetylcholine

Answer 26

A neurotransmitter in the basal forebrain and the mesopontine tegmentum that plays an important role in many of your body’s functions, including muscle movement, memory and cognition, REM sleep, and attention and learning.

Question 27

Acetylcolinesterase

Answer 27

Enzyme that degrades acetylcholine and terminates its action at the neuromuscular junction and synapses.

Question 28

Dopamine

Answer 28

A neurotransmitter in the substantia nigra, the ventral tegmental area, and the hypothalamus that allows one to feel pleasure, satisfaction, and motivation.

Question 29

Serotonin

Answer 29

A neurotransmitter in the raphe nuclei of the midbrain and the GI tract that functions in mood, appetite, sleep, body temperature, and blood.

Question 30

Neuropeptides

Answer 30

A class of neurotransmitters and gut-brain peptides (examples: endorphins and enkephalins).

Question 31

Epilepsy

Answer 31

A disorder in which nerve cell activity in the brain is disturbed, causing seizures.

Question 32

Huntington Disease

Answer 32

Hereditary disorder leading to degeneration of the basal nuclei and the cerebral cortex.

Question 33

Parkinson Disease

Answer 33

Neurodegenerative disorder of the basal nuclei due to an insufficient secretion of the neurotransmitter dopamine; symptoms include tremor and rigid movements.

Question 34

Insomnia

Answer 34

A sleep disorder that results in one having trouble falling asleep, staying asleep, or getting good quality sleep.

Question 35

Alzheimer Disease

Answer 35

Degenerative brain disease resulting in progressive loss of memory and motor control, and increasing dementia.

Question 36

Convergent Nerve Impulse

Answer 36

An electrochemical signal transmitted from various sensory receptors to a single neuron in order to collect, process, and respond to the information.

Question 37

Divergent Nerve Impulse

Answer 37

An electrochemical signal transmitted from one neuron to reach several neurons; example: a single neuron in the CNS may stimulate several motor neurons.