Effects of Drugs

A drug is a substance introduced into the body to provoke a specific physiological response. In addiction, a drug assumes an "essential" biochemical role in the body.

Stimulants increase alertness and body activity, then cause depression. Examples are:

Crack, a cheap, potent form of cocaine, disrupts synapses by overstimulating the postsynaptic cells. Under the influence of this drug, normal impulses to eat and sleep are suppressed, and feelings of pleasure rise.

Depressants and hypnotics lower activity of nerves and parts of the brain. Examples are:

Hallucinogens and marijuana skew sensory perception by interfering with action of neurotransmitters. Examples are:

REVIEW: Sensory axons enter the spinal cord through

REVIEW: Interneurons
a. connect a motor neuron and sensory neuron.
b. determine whether a particular motor neuron is excited or inhibited.
c. become either sensory or motor neurons during development.
d. are described in both a and b.
e. are described by none of the above.

REVIEW: The pathway in a reflex arc is

REVIEW: The resting potential of a neuron is due mostly to

REVIEW:At equilibrium, when the neuron is at rest,

REVIEW: At the peak of the action potential,

REVIEW: The depolarization phase of an action potential is due to

REVIEW: At the neuromuscular junction, which ion triggers the release of neurotransmitter by causing synaptic vesicles to fuse with the presynaptic membrane?

REVIEW: _____, is the enzyme responsible for breaking down acetylcholine into _____ and _____.