Chapter 2 Flashcards
This division of the nervous system is entirely contained within the brain and spinal cord.
central nervous system
A neuron first receives a message in a __________ and passes the message along a long, thin portion of the cell called the __________.
dendrite; axon
__________ are supporting cells with paddle-shaped protrusions that help produce the myelin sheath insulating neurons in the central nervous system.
Oligodendrocytes
__________ are multi-function glial cells that participate in phagocytosis, provide nourishment to neurons, and structurally support neurons in the brain.
Astrocytes
The purpose of the blood–brain barrier is to
block the entrance of some substances into the brain.
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?
Sensory neuron – interneuron – motor neuron – muscle
The neural membrane resting potential is _____.
-70 mV.
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 _____.
diffusion.
__________ push Na+ ions into a cell.
The forces of electrostatic pressure and diffusion
Na+ channels open when the threshold of excitation is reached. This means that these channels are considered:
voltage dependent.
__________ are small rounded structures made of membrane and filled with molecules of neurotransmitter.
Synaptic vesicles
When action potentials are conducted down an axon, what happens inside the terminal buttons?
Synaptic vesicles fuse with the terminal membrane.
In comparison to ionotropic receptors, metabotropic receptors
have effects that occur more slowly.
Influx of __________ or __________ ions result in excitatory postsynaptic potentials (EPSPs).
Na+; Ca2+
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 _____.
reuptake.
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.
Central
When substances are transported from the terminal buttons at the end of the axon back to the soma, this process is referred to as __________.
retrograde axoplasmic transport
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).
neurotransmitter
What are the smallest supporting cells in the central nervous system?
Microglia
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
the blood–brain barrier.
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 _____.
interneurons
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.
hyperpolarizing; depolarizing
A cation would be attracted to _____.
an anion.
The Na+/K+ pump removes __________ Na+ ions from the intracellular fluid and adds __________ K+ ions to the intracellular of a neuron.
3; 2
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 _____.
the same size as for the feather and occur at a faster rate.
Where do synaptic vesicles tend to be found in greatest numbers?
Around the part of the presynaptic membrane that faces the synaptic cleft
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).
positively charged; depolarizing
Autoreceptors are located on the __________.
presynaptic cell
__________ refers to the process of EPSPs and IPSPs interacting to generate excitation or inhibition.
Integration
Neuromodulators differ from neurotransmitters in that _____.
they disperse more widely than do neurotransmitters.
The correct order of the meninges from the surface of the brain outward toward the skull is:
pia, arachnoid, dura.
Cerebrospinal fluid (CSF) serves to:
Surrounds the brain and spinal cord cushioning them.
