BIOL 3204 lecture questions 2

Neurons are the most abundant cell type in the nervous system.

Neurons are the most abundant cell type in the nervous system.

false

The graded potential represents a summation of all the inhibitory and excitatory signals sent from other neurons.

true

Starting from resting potential (-70 mV; "salty banana"), a neuron stimulated by a neurotransmitter that causes K+ channels to open will...

become hyperpolarized and thus be less likely to fire an action potential.

What causes the repolarization phase of the action potential?

K+ exiting the cell through voltage-gated ion channels.

What causes the refractory period and thus the unidirectional flow of the action potential?

K+ channels are slow to close and the Na+/K+ ATPase activity takes time to restore ion concentrations

Why might a squid giant axon be useful for neurophysiology studies?

the large cell size makes it easier to work with than neurons from other animals

If a neuron successfully passes a signal to a postsynaptic cell, which of these events was the last event to occur?

neurotransmitter binding postsynaptic receptors

Successful treatment of depression with SSRIs might involve dampening of serotonergic signalling via...

expression of fewer serotonin receptors on post-synaptic neurons.

Efferent neurons carry signals from the periphery to the central nervous system.

false

Just as tight junctions between epidermal cells protect the surface of your skin, tight junctions between __________ cells lining the blood vessels of the nervous system help control what chemicals get into the brain.

ependymal

Which is an example of a parasympathetic response?

increased secretion of digestive enzymes

What is an example where dual innervation by the SANS and PANS causes cooperative (or synergistic) effects on a target organ?

male orgasm

The parasympathetic nervous system relies upon paravertebral ganglia (i.e. cross wiring) to quickly trigger mass activation when a threat is perceived.

false

The sensory system does all of the following EXCEPT...

projects nerves and signals to effect change in target muscles

Which of these is NOT a characteristic of olfaction?

Olfaction is one of the three senses contributing to our sense of equilibrium.

The taste receptor cells are NOT neurons.

true

Which of the following glial cells is found in the peripheral nervous system?

schwann cells

The conduction of an action potential along an axon...

-is faster for a strong stimulus than a weak stimulus.

-is faster along unmyelinated nerve fibers.

-decreases in amplitude as it is propagated along the axon.

-None of the above.

none

If GABA binds receptors on a post-synaptic cell body, what will likely happen to the membrane potential?

hyperpolarization

Synapses are primarily located in __________ matter. 

grey

Which of the following is the least likely to diffuse across the blood brain barrier?

lipophobic molecule

If the fluid taken from a lumbar puncture is NOT clear and colorless, this could indicate:

either an infection or a brain hemorrhage depending on the color

Which component(s) of the central nervous system is/are responsible for the basic functions of life (e.g., involuntary breathing and heart rate, relaying of sensory and motor signals)?

brainstem, spinal cord

The _______ root and horns receive _______ signals, while the ______ root and horns project _______ signals.

dorsal, afferent, ventral, efferent

Which statements apply to the parasympathetic division of the nervous system?

the parasympathetic division dominates during "resting and digesting" AND its ganglia are on or near the target organs.

"Dual innervation" refers to an organ receiving..

both sympathetic and parasympathetic nerves.

which type of receptors adapt slowly to constant stimulation

tonic

the case of phineas gage shows that each region of the brain is highly specialized, hard-wired for life, and CANNOT change after development

false

successful treatment of depression with SSRIs might involve dampening of serotonergic signalling via..

expression of fewer serotonin receptors on post-synaptic neurons

what type of channel is activated to cause an action potential

voltage gated ion channel