Chapter 2

Question 1

This division of the nervous system is entirely contained within the brain and spinal cord.

Answer 1

central nervous system

Question 2

A neuron first receives a message in a __________ and passes the message along a long, thin portion of the cell called the __________.

Answer 2

dendrite; axon

Question 3

__________ are supporting cells with paddle-shaped protrusions that help produce the myelin sheath insulating neurons in the central nervous system.

Answer 3

Oligodendrocytes

Question 4

__________ are multi-function glial cells that participate in phagocytosis, provide nourishment to neurons, and structurally support neurons in the brain.

Answer 4

Astrocytes

Question 5

The purpose of the blood–brain barrier is to

Answer 5

block the entrance of some substances into the brain.

Question 6

As you study for your neuroscience exam, you feel a tickle on your arm. You see a large spider and you jerk your arm automatically. What is the neural path for this action?

Answer 6

Sensory neuron – interneuron – motor neuron – muscle

Question 7

The neural membrane resting potential is _____.

Answer 7

-70 mV.

Question 8

When students enter a classroom, they tend to spread themselves throughout the room (provided there are enough desks to do so). In biological terms, this effect would be most similar to _____.

Answer 8

diffusion.

Question 9

__________ push Na+ ions into a cell.

Answer 9

The forces of electrostatic pressure and diffusion

Question 10

Na+ channels open when the threshold of excitation is reached. This means that these channels are considered:

Answer 10

voltage dependent.

Question 11

__________ are small rounded structures made of membrane and filled with molecules of neurotransmitter.

Answer 11

Synaptic vesicles

Question 12

When action potentials are conducted down an axon, what happens inside the terminal buttons?

Answer 12

Synaptic vesicles fuse with the terminal membrane.

Question 13

In comparison to ionotropic receptors, metabotropic receptors

Answer 13

have effects that occur more slowly.

Question 14

Influx of __________ or __________ ions result in excitatory postsynaptic potentials (EPSPs).

Answer 14

Na+; Ca2+

Question 15

After release of a neurotransmitter into the synapse, the neurotransmitter is transported by the presynaptic membrane back into the cell to be reused. This process is called _____.

Answer 15

reuptake.

Question 16

Sally’s stomach begins to rumble, reminding her that she skipped breakfast this morning. This hunger signal is sent to Sally’s brain, which is part of her __________ nervous system.

Answer 16

Central

Question 17

When substances are transported from the terminal buttons at the end of the axon back to the soma, this process is referred to as __________.

Answer 17

retrograde axoplasmic transport

Question 18

In order to cross the synapse between two cells, a substance called __________ is released from the first cell (presynaptic) to activate or inhibit the second cell (postsynaptic).

Answer 18

neurotransmitter

Question 19

What are the smallest supporting cells in the central nervous system?

Answer 19

Microglia

Question 20

A scan shows that a particular substance has spread throughout Xiao Ling’s body via the bloodstream but has not entered her brain. This finding demonstrates the existence of

Answer 20

the blood–brain barrier.

Question 21

Herlinda drinks hot coffee. Although the pain is so great that her reflex is to spit out the coffee, she does not do so. The reflex to spit out the coffee is inhibited by the release of an inhibitory neurotransmitter by the _____.

Answer 21

interneurons

Question 22

If the inner voltage of a cell is -70 mV and application of stimulation results in a -95 mV charge, the stimulation had a __________ effect. On the other hand, a resultant charge of +40 mV would be a __________ effect.

Answer 22

hyperpolarizing; depolarizing

Question 23

A cation would be attracted to _____.

Answer 23

an anion.

Question 24

The Na+/K+ pump removes __________ Na+ ions from the intracellular fluid and adds __________ K+ ions to the intracellular of a neuron.

Answer 24

3; 2

Question 25

Dropping a bowling ball or a feather on your foot will produce differences in action potentials. The action potentials associated with the bowling ball would be _____.

Answer 25

the same size as for the feather and occur at a faster rate.

Question 26

Where do synaptic vesicles tend to be found in greatest numbers?

Answer 26

Around the part of the presynaptic membrane that faces the synaptic cleft

Question 27

Calcium ions (Ca2+) are __________ and in highest concentration outside the cell. This means they have the effect of __________ the membrane, thereby contributing to excitatory postsynaptic potentials (EPSPs).

Answer 27

positively charged; depolarizing

Question 28

Autoreceptors are located on the __________.

Answer 28

presynaptic cell

Question 29

__________ refers to the process of EPSPs and IPSPs interacting to generate excitation or inhibition.

Answer 29

Integration

Question 30

Neuromodulators differ from neurotransmitters in that _____.

Answer 30

they disperse more widely than do neurotransmitters.

Question 31

The correct order of the meninges from the surface of the brain outward toward the skull is:

Answer 31

pia, arachnoid, dura.

Question 32

Cerebrospinal fluid (CSF) serves to:

Answer 32

Surrounds the brain and spinal cord cushioning them.