CH1

Question 1

Has its soma in the spinal cord

Receives excitation from other neurons

Conducts impulses along its axon to a muscle or gland

Answer 1

motor neuron

Question 2

Is specialized at one end to be highly sensitive to a particular type of stimulation (touch, light, sound, etc.)

Answer 2

sensory neuron

Question 3

Components of All Neurons

Answer 3

Dendrites

Soma/cell body

Axon

Presynaptic terminals

Question 4

Branching fibers with a surface lined with synaptic receptors responsible for bringing information into the neuron

Answer 4

Dendrites

Question 5

Contains the nucleus, mitochondria, and ribosomes

Responsible for the metabolic work of the neuron

Covered with synapses on its surface in many neurons

Answer 5

Cell Body/Soma

Question 6

Thin fiber of a neuron responsible for transmitting nerve impulses toward other neurons, organs, or muscles

Maybe have a myelin sheath, an insulating material that contains interruptions in the sheath known as nodes of Ranvier

Answer 6

Axons

Question 7

Help synchronize the activity of the axon by wrapping around the presynaptic terminal and taking up chemicals released by the axon

Responsible for dilating blood vessels to bring more nutrients into brain areas with heightened activity

Answer 7

Astrocytes

Question 8

Remove waste material, viruses, and fungi from the brain

Also remove dead, dying, or damaged neurons

Answer 8

Microglia

Question 9

Build the myelin sheath that surrounds and insulates certain vertebrate axons

Answer 9

Oligodendrocytes (in the brain and spinal cord) and

Schwann cells (in the periphery of the body)

Question 10

Guide the migration of neurons and the growth of their axons and dendrites during embryonic development

Answer 10

Radial glia

Question 11

A mechanism that surrounds the brain and blocks most chemicals from entering

Answer 11

The Blood-Brain Barrier

Question 12

The protein-mediated process that expends energy to pump chemicals from the blood into the brain

Answer 12

Active Transport

Question 13

Prolonged thiamine deficiency leads to death of neurons as seen in

Answer 13

Korsakoff’s syndrome

Question 14

The electrical message that is transmitted down the axon of a neuron

Answer 14

The Nerve Impulse

Question 15

At rest, the membrane maintains an electrical gradient known as

Answer 15

polarization

Question 16

The inside of the membrane is slightly negative with respect to the outside (approximately

Answer 16

-70 millivolts

Question 17

increasing the polarization or the difference between the electrical charge of two places

Answer 17

Hyperpolarization

Question 18

decreasing the polarization toward zero

Answer 18

Depolarization

Question 19

a level above which any stimulation produces a massive depolarization

Answer 19

The threshold of excitation

Question 20

Membrane channels whose permeability depends upon the voltage difference across the membrane

Answer 20

Sodium and potassium channels

Question 21

Local anesthetic drugs block sodium channels and therefore prevent action potentials from occurring

Answer 21

Novocain and Xylocaine

Question 22

States that the amplitude and velocity of an action potential are independent of the intensity of the stimulus that initiated it.

Answer 22

The all-or-none law

Question 23

the first part of the period in which the membrane cannot produce an action potential

Answer 23

The absolute refractory period

Question 24

the second part, in which it takes a stronger than usual stimulus to trigger an action potential

Answer 24

The relative refractory period