Substance Abuse Chapter 4 study questions

The process of maintaining our internal environment within certain limits is called ___.

homeostasis

In addition to neurons, the brain contains an even larger number of another cell type known as ___.

glia

Which of these is NOT one of the four important regions found in every neuron?
-cell body
-dendrites
-axon
-glia

glia

Gated ion channels for sodium and potassium open and close in rapid succession, causing the neuron to depolarize and then return to its normal resting level, during each ___.

action potential

Cocaine selectively blocks Na+ (sodium) channels, which is the mechanism that leads to ___.

local anesthetic effects

The disease ___ results from a loss of myelin wrappings.

multiple sclerosis

Parasympathetic and sympathetic refer to the two branches of the ___.

autonomic nervous system

Parkinson’s disease produces tremors and muscular rigidity because of damage to ___.

dopamine neurons in the nigrostriatal pathway

The neurotransmitter at the end organ of the sympathetic branch of the autonomic nervous system is ___.

norepinephrine

The ___ is an important link between the brain and the pituitary gland, and is involved in feeding, drinking, temperature regulation and sexual behavior.

hypothalmus

Neural centers controlling vomiting and respiration are found in the ___.

Brain stem

Which chemical pathway appears to be important both in some types of psychotic behavior and in the reinforcing properties of various drugs?

mesolimbic dopamine pathway

Weight control, aggression, impassivity and psychological depression have all been associated with ___.

serotonin pathways

Natural chemicals in the brain that produce effects similar to those of morphine and other opium-derived drugs are called ___.

endorphins

The process in which enzymes within neurons convert precursors into neurotransmitter molecules is called ___.

synthesis

Neurotransmitter molecules are released into the small space between two neurons called the ___.

synapse

Specialized structures that recognize neurotransmitter molecules and when activated may cause a change in the electrical activity of the neuron, are called ___.

receptors

Which of the following neurotransmitters is found in most parts of the brain and is considered inhibitory?

GABA

Whether the effect of a neurotransmitter is excitatory or inhibitory depends on ___.

the type of receptor

Drugs can effect neurotransmitter systems in two main ways: either by altering the availability of the neurotransmitter in the synapse, or by ___.

acting directly on the receptors

Suppose you wanted to prescribe a hypothetical drug that would have an overall excitatory effect on the nervous system. Which would you choose?
-a glutamate metabolizer
-a dopamine metabolizer
-a GABA antagonist
-a norepinephrine antagonist

a GABA antagonist

The brain imaging technique that involves injection of radioactive chemicals in order to measure brain function is called ___.

positron emission tomography (PET)

T or F. Unlike neurons, glial cells in the brain are purely for support and are incapable of communication with each other.

False

T or F. The complex branching parts of a neuron that receive information from other neurons are called dendrites.

True

T or F. In the neuron, neurotransmitters are stored in the myelin sheaths.

False

T or F. It is possible to have an action potential that is relatively small in magnitude (if few channels are open).

True

T or F. Parkinson’s patients are often treated with dopamine because L-dopa cannot cross the blood-brain barrier.

False

T or F. One of the main ways that drugs can affect neurotransmitter systems is by cutting off blood flow to a specific brain structure.

False

MRI and PET are two types of neurotransmitter chemicals.

False

GABA and glutamate are similar in that they are found throughout the brain and are primarily inhibitory neurotransmitters.

False

Describe the structure of a neuron.

Neurons have four regions: -cell body: containing the nucleus -dendrites: treelike features that extend from the cell body and contain receptors -axon: long slender extension of the cell body responsible for conducting the action potential to the axon terminals -axon terminals: bulbous structures at the end of the axon where neurotransmitters are stored in vesicles

Describe the differing effects of the sympathetic and parasympathetic branches of the autonomic nervous system.

Sympathetic-"fight or flight" reactions: opens bronchi, decreases blood supply to skin, increases heart rate, reduces stomach motility, dilates pupils Parasympathetic-inhibits heart rate, constricts pupils, increases stomach motility, dilates skin blood vessels, constricts bronchi

What are the steps involved in the life cycle of a neurotransmitter?

-uptake of precursors -synthesis of transmitter -storage in vesicles -release into the synapse -interaction with the receptor -reuptake into the releasing neuron -metabolism by enzymes

The actions of drugs on neurotransmitter systems can be divided into two main types. What are they?

Drugs can alter the availability of the neurotransmitter in the synapse or affect the receptors by: -mimicking the action of the neurotransmitter -occupying the receptor preventing the neurotransmitter from activating