Psyc Ch. 1

Question 1

Active Transport

Answer 1

a protein-mediated process that expends energy to enable a molecule to cross a membrane

Question 2

Afferent Axon

Answer 2

axon that brings information into a structure

Question 3

Astrocytes

Answer 3

star-shaped glia that synchronize the activity of the axons

Question 4

Blood-Brain Barrier

Answer 4

mechanism that excludes most chemicals from the brain

Question 5

Cell Body/Soma

Answer 5

structure containing the nucleus, ribosomes, and mitochondria

Question 6

Dendrites

Answer 6

branching fibers from a neuron that receive information from other neurons

Question 7

Efferent Axon

Answer 7

neuron that carries information away from a structure

Question 8

Endoplasmic Reticulum

Answer 8

network of thin tubes that transport newly synthesized proteins to other locations

Question 9

Glia

Answer 9

type of cell in the nervous system that, in contrast to neurons, does not conduct impulses over long distances

Question 10

Glucose

Answer 10

a simple sugar

Question 11

Intrinsic Neuron/Interneuron

Answer 11

neuron whose axons and dendrites are all confined within a given structure

Question 12

Membrane

Answer 12

structure that separates the inside of the cell from the outside environment

Question 13

Microglia

Answer 13

cells that remove waste material and other microorganisms from the nervous system

Question 14

Mitochondrion

Answer 14

structure that performs metabolic activities

Question 15

Motor Neuron

Answer 15

neuron that receives excitation from other neurons and conducts impulses to a muscle

Question 16

Myelin Sheath

Answer 16

insulating material that covers vertebrate axon

Question 17

Neurons

Answer 17

cells that receive information and transmit it to other cells

Question 18

nodes of Ranvier

Answer 18

interruptions in the myelin sheath of vertebrate axons

Question 19

Nucleus

Answer 19

structure that contains the chromosomes

Question 20

Oligodendrocytes

Answer 20

glia cells that build myelin sheaths

Question 21

Presynaptic Terminal

Answer 21

(end bulb or bouton) point where an axon releases chemicals

Question 22

Radial Glia

Answer 22

cells that guide the migration of neurons and the growth of axons and dendrites during embryological development

Question 23

Ribosomes

Answer 23

sites for cell synthesization of new protein molecules Ritalin. See Methylphenidate RNA. See Ribonucleic acid

Question 24

Schwann Cells

Answer 24

glia cells that build myelin sheaths SCN. See Suprachiasmatic nucleus

Question 25

Sensory Neuron

Answer 25

neuron that is highly sensitive to a specific type of stimulation

Question 26

Thiamine

Answer 26

B1, vitamin, necessary to use glucose

Question 27

Absolute Refactory Period

Answer 27

a time when the membrane is unable to produce an action potential

Question 28

Action Potentials

Answer 28

all-or-none message sent by an axon

Question 29

All-or-none Law

Answer 29

principle that the amplitude and velocity of an action potential are independent of the stimulus that initiated it

Question 30

Concentration Gradient

Answer 30

difference in distribution of ions across the neuron’s membrane

Question 31

Depolarize

Answer 31

(depolarization) to reduce polarization toward zero across a membrane Depression. See Antidepressant drugs; Major depression

Question 32

Electrical Gradient

Answer 32

difference in electrical charges between the inside and outside of the cell

Question 33

Graded Potential

Answer 33

a membrane potential that varies in magnitude in proportion to the intensity of the stimulus

Question 34

Hyperpolarization

Answer 34

increased polarization across a membrane

Question 35

Local Anesthetic

Answer 35

drug that attaches to the sodium channels of the membrane, stopping action potentials

Question 36

Local Neurons

Answer 36

neurons without an axon

Question 37

Myelin

Answer 37

an insulating material composed of fats and proteins

Question 38

Myelinated Axons

Answer 38

axons covered with myelin sheaths

Question 39

Polarization

Answer 39

difference in electrical charges between the inside and outside of the cell

Question 40

Propagation of the action potential

Answer 40

transmission of an action potential down an axon

Question 41

Refractory Period

Answer 41

time when the cell resists the production of further action potentials

Question 42

Relative Refractory Period

Answer 42

time after the absolute refractory period that requires a stronger stimulus to initiate an action potential

Question 43

Resting Potential

Answer 43

condition of a neuron’s membrane when it has not been stimulated or inhibited

Question 44

Saltatory Conduction

Answer 44

the jumping of action potentials from node to node

Question 45

Selective Permeability

Answer 45

ability of some chemicals to pass more freely than others through a membrane

Question 46

Sodium-Potassium Pump

Answer 46

mechanism that actively transports sodium ions out of the cell while drawing in two potassium ions

Question 47

Threshold

Answer 47

minimum amount of membrane depolarization necessary to trigger an action potential

Question 48

Voltage-Gated Channels

Answer 48

membrane channel whose permeability to sodium (or some other ion) depends on the voltage difference across the membrane