\" In a synapse between two neurons, a postsynaptic potential isa graded potential that is the result of a neurotransmitterreleased into the synaptic cleft. \"

True

False

QUESTION 17

Which neuron would stimulate a muscle contraction?

		Multipolar
		Unipolar
		Bipolar

QUESTION 18

Which neuron is a sensory neuron found in a reflex arc?

		Multipolar
		Unipolar
		Bipolar

QUESTION 19

Which neuron is never myelinated?

		Multipolar
		Unipolar
		Bipolar

QUESTION 20

\" In a reflex arc, which neuron has its cell body inside thespinal cord?\"

		Multipolar
		Unipolar
		Bipolar

QUESTION 21

The all-or-none phenomenon as applied to nerve conduction statesthat the whole nerve cell must be stimulated for conduction to takeplace.

True

False

QUESTION 22

Neurons in the CNS are organized into functional groups.

True

False

QUESTION 23

Strong stimuli cause the amplitude of action potentialsgenerated to increase.

True

False

QUESTION 24

In myelinated axons the charge propagation through themyelinated internodal regions occurs via passive charge diffusiononly and the signal degrades over distance.

True

False

QUESTION 25

A single postsynaptic potential in a neuron not usually largeenough to trigger an action potential.

True

False

QUESTION 26

\" An action potential traveling toward a synapse opens calciumion channels at the presynaptic end, which in turn promotes fusionof synaptic vesicles to the axonal membrane.\"

True

False

QUESTION 27

Axon diameter and degree of myelination determine nerve impulseconduction velocity.

True

False

QUESTION 28

\"If the membrane potential at the axon hillock of thepostsynaptic neuron reaches threshold level, an action potentialwill be produced.\"

True

False

QUESTION 29

Acetylcholine is actively transported from the pre-synapticmembrane to the post - synaptic membrane.

True

False

QUESTION 30

The area between the pre-synaptic nerve cell and thepost-synaptic muscle cell is termed the synaptic cleft.

True

False

QUESTION 31

Receptors on the post-synaptic cell membrane that bind theneurotransmitter are voltage-gated.

True

False

QUESTION 32

\"Their methods are different, but ____________ in the CNS and____________ in the PNS perform similar functions.\"

		astrocytes; neurolemmocytes (Schwann cells)
		oligodendrocytes; neurolemmocytes (Schwann cells)
		microglia; satellite cells
		ependymal cells; satellite cells

QUESTION 33

Which glial cells behave much like certain leukocytes?

		microglia
		ependymal cells
		oligodendrocytes
		satellite cells

QUESTION 34

In terms of nerve impulse conduction, unmyelinated is to____________ as myelinated is to ____________.

		oligodendrocytes; Schwann cells
		saltatory; action potentials
		continuous; saltatory
		saltatory; continuous

QUESTION 35

An action potential involves ____________ across a neuron'splasma membrane.

		changes in voltage
		movement of ions
		both a and b
		neither a nor b

QUESTION 36

\"At a chemical synapse, ____________ are found only in theplasma membrane of the ____________ cell.\"

		neurotransmitters; postsynaptic
		receptor proteins; postsynaptic
		ligand-gated channels; presynaptic
		receptor proteins; presynaptic

QUESTION 37

With regard to control of muscle cells and glands, ____________is to involuntary as ____________ is to voluntary.

		somatic; visceral
		somatic; peripheral
		autonomic; somatic
		central; peripheral

QUESTION 38

Increased dietary intake of vitamin B12Êand ____________ duringpregnancy can dramatically reduce the incidence of neural tubedefects such as ____________.

		ascorbic acid (vitamin C); neuritis and demyelination
		folic acid (folate); anencephaly and spina bifida
		pantothenic acid; amyotrophic lateral sclerosis
		iron; Guillain-Barr syndrome

QUESTION 39

Which statement about synapses between neurons isFALSE?

		An excitatory postsynaptic potential occurs if the binding ofthe neurotransmitter to its receptor causes Na+ channels toopen.
		If the excitatory and inhibitory effects are equal this willtrigger an action potential at the axon hillock of the postsynapticneuron.
		In an inhibitory postsynaptic potential the postsynapticmembrane becomes hyperpolarized.
		An inhibitory postsynaptic potential occurs if the binding ofthe neurotransmitter to its receptor causes K+ channels toopen.

QUESTION 40

The region of the brain containing commissural fibers crossingbetween the right and left cerebral hemispheres is the_________.

		Pons
		Septum pellucidum
		Corpus callosum
		Thalamus