BioPsych Unit 2 Quiz

The main feature that distinguishes a neuron from other animal cells is that a neuron has:

A distinctive shape

With respect to drug effects, "efficacy" means the tendency of a drug to

Activate a receptor

A drug that mimics or increases the effects of a neurotransmitter is called an:

Agonist

When a membrane is at rest, what attracts potassium ions to the inside of the cell?

An electrical gradient

The membrane of a neuron is specialized to:

Control the exchange of chemicals between the inside and outside of the cell

Most habit-forming drugs activate which type of synapse?

Dopamine

The primary difference between and EPSP and an action potential is that

EPSPs are sub-threshold events that decay over time and space

What are the nodes of Ranvier?

Gaps in the myelin sheath

A graded depolarization is known as an?

IPSP

The most important consideration in developing a drug that will act in the brain is:

If the drug will cross the blood-brain barrier

Saltatory conduction ____ the velocity of action potentials, and _____ the amount of energy used by the neuron.

Increases, decreases

The insulating material which covers many vertebrate axons is called the:

Myelin sheath

What are the two kinds of cells in the nervous system?

Neurons and glia

According to the all-or-none law:

Once an axon reaches threshold, the amplitude and velocity of an action potential are nearly equal each time

An action potential causes the release of neurotransmitters by:

Opening calcium pores in the membrane

Just after the peak of the action potential, what movement of ions restores the membrane to approximately the resting potential?

Potassium ions leave the cell

Which of the following would produce spatial summation?

Present two or more weak stimuli at the same time

Compared to passive transport, the major disadvantage of active transport is that it:

Requires expenditure of energy

What is the difference in voltage called that typically exists between the inside and the outside of a neuron?

Resting potential

When a neuron's membrane is at rest, which of the following molecules crosses through it MOST slowly?

Sodium

The action potential of a neuron depends mostly on what movement of ions?

Sodium ions entering the cell

Chemicals (ions) that cannot flow freely across a cell membrane enter a neuron through:

Specialized protein channels

Specialized junctions between neurons are called:

Synapses

Which of the following is the correct sequence of chemical events at a synapse?

Synthesis, transport, release, reuptake

A certain weak stimulus produces no reflexive response, but a rapid repetition of that stimulus may produce such a response. What is the phenomenon called?

Temporal summation