General Psychology

Question 1

Synaptic Transmission

Answer 1

Process when an action potential reaches the end of an axon at a synapse, the signal is transformed into a chemical signal with the release of neurotransmitter into the synaptic cleft

Question 2

Neuron

Answer 2

The basic functional and structural unit of the nervous system

Question 3

Soma

Answer 3

Central cell body of neurons; contains nucleus and is where most of the biosynthesis activity takes place

Question 4

Dendrites and axon

Answer 4

Slender projections extending from the cell body

Question 5

Bipolar

Answer 5

Neurons with only one dendrite

Question 6

Multipolar

Answer 6

Neurons with many dendrites

Question 7

Synaptic knobs

Answer 7

End of axons that for connection with target cells

Question 8

Synaptic cleft

Answer 8

Small gap between neuron and target cell that chemical messengers are released in to and travel across

Question 9

Nerve

Answer 9

A bundle of many different axons from different neurons

Question 10

Action Potentials

Answer 10

Localized area of depolarization of the plasma membrane that travels in a wave-like manner along an axon

Question 11

Resting Membrane Potential

Answer 11

electric potential across the plasma membrane of approximate -70 mV (interior of cell is negatively charged with respect to exterior)

Question 12

Na+/K+ ATPase

Answer 12

pumps three sodium ions out of the cell and two potassium ions into the cell with hydrolysis of one ATP molecule (primary active transport)

Question 13

Leak channels

Answer 13

channels that are open all the time, that simply allow ions to leak across the membrane according to their gradient

Question 14

Depolarization

Answer 14

A change in membrane potential from the resting membrane potential to a less negative, or even positive, potential

Question 15

Repolarization

Answer 15

after depolarization, when the membrane potential returns to normal

Question 16

Voltage-gated sodium channels

Answer 16

In response to a change in the membrane potential, open to allow sodium ions to flow down their gradient into the cell and depolarize that section of membrane

Question 17

Myelin

Answer 17

insulating sheath wrapping neurons

Question 18

Schwann Cells

Answer 18

glial cells that create myelin sheath; PNS

Question 19

nodes of Ranvier

Answer 19

periodic gaps in myelin sheath where voltage-gate sodium and potassium channels are located

Question 20

Saltatory Conduction

Answer 20

rapid jumping conduction in myelinated axons

Question 21

Glial Cells

Answer 21

specialized, non-neuronal cells that typically provide structural and metabolic support to neurons; maintain a resting membrane potential but do not generate action potentials

Question 22

Oligodendrocytes

Answer 22

CNS; form myelin; increase speed of conduction of APs along axon

Question 23

Astrocytes

Answer 23

CNS; guide neuronal development; regulate synaptic communication via regulation of neurotransmitter levels

Question 24

Microglia

Answer 24

CNS; remove dead cells and debris

Question 25

Ependymal Cells

Answer 25

CNS; produce and circulate cerebrospinal fluid

Question 26

Equilibrium Potential

Answer 26

membrane potential which the gradient driving force does not exist (as in action potentials); no net movement of ions across the membrane

Question 27

Refractory

Answer 27

the passage of one action potential makes the neuron unresponsive to membrane depolarization and unable to transmit another action potential for a short period of time

Question 28

Absolute Refractory Potential

Answer 28

a neuron will not fire another action potential no matter how strong a membrane depolarization is induced; during this time, the voltage-gated sodium channels have been inactivated

Question 29

Relative Refractory Period

Answer 29

a neuron can be induced to transmit an action potential, but the depolarization required is greater than normal because the membrane is hyperpolarized

Question 30

Hyperpolarized

Answer 30

a brief period after repolarization in which the membrane potential is more negative than the resting potential caused by the voltage-gated potassium channels that have not been closed yet

Question 31

Synaspe

Answer 31

Junction between the axon terminus of a neuron and the dendrites, soma, or axon of a second neuron

Question 32

Electrical Synapses

Answer 32

occur when the cytoplasms of two cells are joined by action potentials (smooth and cardiac muscle)

Question 33

Chemical Synapses

Answer 33

found at the ends of axons where they meet their target cells

Question 34

Excitatory

Answer 34

neurotransmitter opens a channel that depolarizes the postsynaptic membrane

Question 35

Inhibitory

Answer 35

neurotransmitter that induces hyperpolarization of the postsynaptic membrane

Question 36

Temporal Summation

Answer 36

in which a presynaptic neuron fire action potentials so rapidly that EPSPs and IPSPs pile up on each other

Question 37

Spatial Summation

Answer 37

EPSPs and IPSPs from all of the synapses on the postsynaptic membrane are summed at a given moment in time

Question 38

Motor Neurons

Answer 38

carry information from the nervous system toward organs which can act upon information (known as effectors) (Efferent Neurons)

Question 39

Sensory Neurons

Answer 39

carry information toward the central nervous system (Afferent neurons)

Question 40

Reflex

Answer 40

direct motor response to sensory input which occurs without conscious thought

Question 41

Monosynaptic reflex arc

Answer 41

involving only two neurons and one synapse

Question 42

Somatic

Answer 42

conscious sensation and deliberate, voluntary movement of skeletal muscle

Question 43

Autonomic

Answer 43

digestion, metabolism, circulation, perspiration and other involuntary processes

Question 44

Ganglia

Answer 44

somas located outside the central nervous system

Question 45

Cerebrospinal Fluid

Answer 45

a clear liquid that serves various functions such as shock absorption and exchange of nutrients and waste with the CNS

Question 46

Medulla

Answer 46

(hindbrain) connects to spinal cord; functions in relaying information between other areas of the brain, and regulates vital autonomic functions such as blood pressure and digestive functions and respiratory rhythmicity centers

Question 47

Pons

Answer 47

(hindbrain) located below the midbrain and above the medulla oblongata; connection point between the brain stem and the cerebellum; controls some autonomic functions and coordinates movement; plays role in balance and antigravity posture

Question 48

Cerebellum

Answer 48

located behind pons and below cerebral hemispheres; integrating center, complex movements are coordinated

Question 49

Midbrain

Answer 49

relay for visual and auditory information and contains much of the reticular activating system (responsible for arousal and wakefulness)

Question 50

Spinal Cord

Answer 50

Pathway for information to and from the brain; responsible for simple spinal reflexes and primitive processes such as walking, urination, and sex organ function

Question 51

Hindbrain

Answer 51

medulla, pons, and the cerebellum

Question 52

Brainstem

Answer 52

medulla, pons, and midbrain