48 prac

Neurons communicate by ____

short-distance chemical signals and long-distance electrical signals

What are ganglia

clusters of nerve cell bodies

A neuron that transmits an impulse to the central nervous system after the neuron is stimulated by the environment is called a(n) _________

sensory neuron

Which of the following is specifically a part or a function of the central nervous system?

integration

The part of a neuron that carries nerve impulses toward the cell body is called a(n) _____

dendrite

Cells that provide metabolic and structural support to the neurons are called _____

glia

If your fingers touch a hot stove and you suddenly pull back, you have experienced a reflex. What is the correct order of the information processing in this reflex

sensory input, integration, motor output

Which of the following statements is correct
A neuron only has a single axon.

Axons receive signals from other neurons.

The peripheral nervous system is most closely associated with interneurons.

Dendrites branch off axons.

A neuron only has a single axon.

In descriptions of synapse organization, which type of cell is the transmitting neuron and which type of neuron, muscle, or gland cell receives the signal

presynaptic ... postsynaptic

Which of the following statements is correct?

The nucleus of a neuron is located in the axon hillock.

Sensory neurons transmit signals to muscle cells.

The vast majority of neurons in the brain are sensory neurons.

None of the listed responses is correct.

None of the listed responses is correct.

Which of the following statements about the resting potential is true
Inside the cell, the concentration of potassium is much higher than the concentration of sodium.

The concentration of sodium is much higher inside the cell than outside.

The chloride-hydrogen pump plays a role in maintaining the resting potential.

The neuron's plasma membrane is much more permeable to sodium than to potassium

nside the cell, the concentration of potassium is much higher than the concentration of sodium.

The sodium-potassium pump ________

expels sodium from the cell

Which of the following statements is true?

Concentration gradients of proteins across the plasma membrane represent potential energy.

Ion channels are selectively permeable, permitting only certain ions to pass.

Ion channels allow ions to cross the cell membrane against their concentration gradients.

All cells have an equilibrium potential, which is a difference in electrical charges across their plasma membrane.

Ion channels are selectively permeable, permitting only certain ions to pass.

Blocking potassium ion channels in a mammalian cell membrane would _____

decrease the magnitude of the membrane potential

What is an increase in the magnitude of the membrane potential called?

hyperpolarization

A drug that causes potassium to leak out of a neuron, increasing the positive charge on the outside, would ____

inhibit transmission of nerve signals by the neuron

Threshold is of great significance in the physiology of neurons. What happens if threshold is NOT reached?

positive-feedback depolarization will not occur

Schwann cells make up the _______

myelin sheath in axons of the PNS (peripheral nervous system)

An action potential is ____

a traveling wave of depolarization in the neuron membrane

The period in which an axon membrane CANNOT generate an action potential is called ____

the refractory period

Saltatory conduction means that the membrane potential changes ______

only at the nodes of Ranvier

Action potentials are generated along a neuron because __

depolarization of the membrane at one point causes an increase of permeability to sodium at the next point

How are neurons structurally adapted to chemically transmit impulses to neighboring neurons?

Axon terminals contain neurotransmitter within synaptic vesicles.

Which of the following statements about the transmission across a typical chemical synapse is true

The binding of neurotransmitter molecules to receptors on the postsynaptic cell membrane results in changes to the behavior of the postsynaptic cell.

Acetylcholinesterase is the enzyme that degrades acetylcholine. What effect on nerve transmission would occur following the administration of a chemical that inhibited acetylcholinesterase?

Continuous excitatory postsynaptic potentials would occur in the postsynaptic neuron.

In humans, making more serotonin available to brain cells typically ____

produces an effect on mood

27

Question 27:Which of the following is a natural pain reliever?

endorphins

Which of the following correctly pairs up a type of synapse and its characteristic?
electrical synapse ... gap junctions

junctional synapses ... ligand-gated ion channels

chemical synapses ... gap junctions

electrical synapse ... neurotransmitters

electrical synapse ... gap junctions

Which of the following neurotransmitters typically has inhibitory effects?
norepinephrine

substance P

GABA (gamma-aminobutyric acid)

glutamate

GABA (gamma-aminobutyric acid)

Which of the following is a mechanism by which neurotransmitters can be rapidly cleared from the synaptic cleft

Neurotransmitters are removed by enzymatic hydrolysis of the neurotransmitter.

The neurotransmitters are transferred to glia to be metabolized.

The neurotransmitters are actively transported back into the presynaptic cells to be repackaged into synaptic vesicles.

Neurotransmitters are removed by simple diffusion.

The interplay of multiple excitatory and inhibitory inputs most affects what part of a neuron?

axon hillock