Chapter 3A Vocab

Question 1

biological psychology

Answer 1

a branch of psychology concerned with the links between biology and behavior

Question 2

neuron

Answer 2

a nerve cell; the basic building block of the nervous system

Question 3

sensory neurons

Answer 3

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

Question 4

motor neurons

Answer 4

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

Question 5

interneurons

Answer 5

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

Question 6

dendrite

Answer 6

bushy branching extensions of a neuron that receive messages and conduct impulses toward the cell body

Question 7

axon

Answer 7

the extension of a neuron ending in terminal fibers through which messages pass to other neurons or to muscles or glands

Question 8

myelin sheath

Answer 8

layer of fatty tissue segmentally encasing the fibrs of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next

Question 9

action potential

Answer 9

a neural impulse; a brief electrical charge that travels down an axon

Question 10

threshold

Answer 10

level of stimulation required to trigger a neural impulse

Question 11

synapse

Answer 11

junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap or synaptic cleft.

Question 12

neurotransmitters

Answer 12

chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse. (p. 55)

Question 13

reuptake

Answer 13

a neurotransmitter’s reabsorption by the sending neuron.

Question 14

endorphins

Answer 14

“morphine within”—natural, opiatelike neurotransmitters linked to pain control and to pleasure.

Question 15

nervous system

Answer 15

the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.

Question 16

central nervous system

Answer 16

brain and spinal cord

Question 17

peripheral nervous system

Answer 17

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

Question 18

nerves

Answer 18

bundled axons that form neural “cables” connecting the central nervous system with muscles, glands, and sense organs.

Question 19

somatic nervous sytem

Answer 19

the division of the peripheral nervous system that controls the body’s skeletal muscles. Also called the skeletal nervous system.

Question 20

autonomic nervous system

Answer 20

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms.

Question 21

sympathetic nervous system

Answer 21

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations.

Question 22

parasympathetic nervous system

Answer 22

the division of the autonomic nervous system that calms the body, conserving its energy.

Question 23

reflex

Answer 23

a simple, automatic response to a sensory stimulus, such as the knee-jerk response.

Question 24

endocrine system

Answer 24

system the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream.

Question 25

hormones

Answer 25

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues.

Question 26

adrenal glands

Answer 26

sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.

Question 27

pituitary gland

Answer 27

the endocrine system’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.