Chapter 40

Summing incoming neural signals is part of (a) reception (b) transmission (c) integration (d) action by effectors (e) afferent neuron transmission

Which of the following are phagocytic cells that remove bacteria and debris from the CNS? (a) Schwann cells (b) axons (c) oligodendrocytes (d) effectors (e) microglia

Most of the neuron cytoplasm is located in the (a) cell body (b) axon (c) dendrites (d) synaptic terminals (e) nodes

Action potentials are transmitted to synaptic terminals by the (a) ganglia (b) axon (c) dendrites (d) cell body (e) nodes

In responding to a stimulus, a motor neuron signals a(an) (a) efferent neuron (b) receptor (c) afferent neuron (d) interneuron (e) effector

The myelin sheath is produced around axons in the PNS by (a) axons (b) neuron cell bodies (c) dendrites (d) Schwann cells (e) oligodendrocytes

Neurotransmitters are released by (a) effectors (b) neuron cell bodies (c) dendrites (d) ganglia (e) synaptic terminals

Which of the following does not contribute to the resting potential of a neuron? (a) sodium-potassium pumps (b) ion channels (c) differences in concentration of ions across the membrane (d) differences in permeability to certain ions (e) graded potentials

Which of the following occurs first when voltage reaches the threshold level? (a) gates of certain voltage-activated ion channels open (b) \(\mathrm{K}^{+}\) channels close (c) the membrane hyperpolarizes (d) neurotransmitter is released (e) neurotransmitter reuptake takes place at the synapse

Saltatory conduction (a) requires more energy than continuous conduction (b) occurs in unmyelinated neurons (c) occurs when the action potential jumps from one node of Ranvier to the next (d) slows transmission of an impulse (e) depends on the presence of GABA

IPSPs (a) excite presynaptic neurons (b) excite postsynaptic neurons (c) can cancel the effects of some EPSPs (d) release large amounts of neurotransmitters (e) are released by postsynaptic cell bodies

A presynaptic neuron in the cerebrum synapses with hundreds of other neurons. This is an example of (a) convergence (b) divergence (c) summation (d) a reverberating circuit (e) a graded potential

During a relative refractory period, (a) IPSPs are generated (b) opioid neurotransmitters are released (c) voltage-activated sodium channels are inactivated (d) an axon can transmit impulses but the threshold is higher (less negative) (e) an axon cannot transmit an action potential

In spatial summation, (a) repeated stimuli cause new EPSPs to develop before previous ones decay (b) divergence occurs at two or more synapses (c) EPSPs and IPSPs cancel each other in the space of the axon (d) two or more EPSPs transmit a summed chemical signal (e) several closely spaced synaptic terminals release neurotransmitter simultaneously