Please answer all questions

1			Impulses are conducted to the soma by the
			A)	axon.
			B)	axon hillock.
			C)	dendrites.
			D)	all of the above.
2			Which of the following neurons are found entirely within the central nervous system?
			A)	Association neuron.
			B)	Efferent neuron.
			C)	Motor neuron.
			D)	Sensory neuron.
3			Myelination of axons within the central nervous system would not occur if which of the following cells were not functional?
			A)	Astrocytes.
			B)	Microglia.
			C)	Oligodendrocytes.
			D)	Schwann cells.
4			The blood-brain barrier would be compromised by damaging
			A)	astrocytes.
			B)	ependymal cells.
			C)	microglia.
			D)	oligodendrocytes.
5			Embryonic development of sensory neurons and maintenance of sympathetic ganglia requires
			A)	glial-derived neurotrophic factor.
			B)	brain-derived neurotrophic factor.
			C)	neurotrophin-4.
			D)	nerve growth factor.
6			Opening only sodium ion channels in a neuron at rest would normally cause
			A)	hyperpolarization.
			B)	depolarization.
			C)	repolarization.
			D)	no change in membrane potential.
7			Which of the following is not true of an action potential?
			A)	Action potentials follow the all-or-none law.
			B)	Positive feedback is important during depolarization.
			C)	Negative feedback is important during repolarization.
			D)	All cells in the body can produce action potentials.
8			Which axon would transmit an action potential most rapidly?
			A)	A 1.3 mm diameter neuron lacking myelin.
			B)	A 1.3 mm diameter neuron lacking myelin.
			C)	A 1.3 mm diameter neuron with myelin.
			D)	All have equal transmission rates.
9			At a chemical synapse
			A)	acetylcholine is always an excitatory neurotransmitter in the autonomic nervous system.
			B)	phosphorylation of synapsins stimulates neurotransmitter release.
			C)	repolarization of the axon terminal allows Ca2+ to flow into the axon terminal.
			D)	neurotransmitters are transported across the synapse by receptor proteins.
10			Muscarinic receptors
			A)	require the action of G-proteins.
			B)	are found on skeletal muscle.
			C)	are functionally linked to Na+ ion channels.
			D)	all of the above.
11			Postsynaptic potentials
			A)	always induce action potentials.
			B)	lack refractory periods.
			C)	are always excitatory.
			D)	are always inhibitory.
12			Tetrodotoxin would directly
			A)	block depolarization of excitable cells.
			B)	block repolarization of excitable cells.
			C)	prevent neurotransmitter release.
			D)	inhibit acetylcholinesterase.
13			Blocking the reuptake of dopamine would induce effects similar to
			A)	Parkinson's disease.
			B)	multiple sclerosis.
			C)	cocaine use.
			D)	Alzheimer's disease.
14			Regarding synaptic cell activation
			A)	summation of postsynaptic potentials may be related to the timing of neurotransmitter release.
			B)	summation of postsynaptic potentials may be related to the site of neurotransmitter release.
			C)	summation may involve both inhibitory and excitatory postsynaptic potentials.
			D)	all of the above.
15			Endogenous opioids
			A)	induce effects which are complimented by naloxone.
			B)	are produced by all cells of the body.
			C)	can block the transmission of pain.
			D)	all of the above.