Biopsychology 1
contributed most to Cajal's ability to find that neurons are separate from one another
Camillo Golgi's cell staining method
physiological
Explaining differences in running speed as a function of differences in muscle fiber types
ionotropic
Glutamate opens sodium gates, enabling sodium ions to enter the postsynaptic cell
functional example
Having camouflage that matches an animal's typical surroundings in order to provide protection from predators
Suppose you were bitten by a black widow spider whose venom increases the release of acetylcholine from the presynaptic terminal. Which of the following treatments would be most effective?
Increase the activity of acetylcholinesterase.
once an action potential starts
It is regenerated at other points along the axon
selective permeability
Only certain molecules are allowed to cross the membrane freely
Why do neurons rely so heavily on glucose as their source of nutrition
Other fuels do not readily cross the blood-brain barrier
Which of the following would produce spatial summation
Present two or more weak stimuli at the same time
temporal summation
Sherrington found that repeated stimuli within a brief time have a cumulative effect
axon
The information sender of the neuron, which conveys an impulse toward either other neurons or a gland or muscle
exocytosis
The neuron excretes neurotransmitter through its membrane
NOT true of axons
They carry information toward the soma
How do most biological psychologists feel regarding the use of animals in research
They use animals only if the potential benefits to humans outweigh the costs to the animals
freely flow across a cell membrane
Water, oxygen and carbon dioxide
all-or-none law
a neuron produces an action potential of maximal strength, or none at all
most likely to suffer from a thiamine deficiency
alcoholics
Protein channels
allow small charged molecules to cross the cell membrane
When a membrane is at rest, what attracts potassium ions to the inside of the cell
an electrical gradient
The chemicals used as neurotransmitters in humans are found in
apparently all or nearly all other species
"Second messengers" carry their messages to
areas within the postsynaptic cell
Neurons typically have one ____, but many ____
axon; dendrites
biological psychology concerns
brain functioning
Dendrites
branching fibers that get narrower near their ends
Schwann cells
builds myelin sheaths around axons in the periphery of the body
When an action potential reaches the end of an axon, the depolarization causes what ionic movement in the presynaptic cell
calcium into the cell
Voltage-activated channels
channels for which a change in the voltage across the membrane alters their permeability
reflex arc
circuit from sensory neuron to muscle response
Loewi demonstrated that synapses operate by the release of chemicals. He did this by:
collecting fluid from a stimulated frog's heart, transferring it to another frog's heart, and measuring that heart rate
the membrane
composed of two layers of fat molecules that are free to flow around one another
EPSPs
decay over time and space
Activation of autoreceptors tends to
decrease further neurotransmitter release
Multiple sclerosis
demyelinating diseases
Many neurons release neuropeptides mostly from the
dendrites
Ontogenetic Explanation
describes how a structure or behavior develops, including the influences of genes, nutrition, experiences, and their interactions
polarized
difference in electrical potential between the inside and the outside of the membrane
dispute between abolitionists and animal researchers
dispute between two ethical positions
Minimalists
do not tolerate any kind of animal research
The function of an Institutional Animal Care and Use Committee
evaluate proposed experiments to ensure that they minimize pain and discomfort
Depolarization is to ____ as hyperpolarization is to ____.
excitation; inhibition
cell membrane is composed of two layers of
fat
Neurotransmitter is to ____ as cyclic AMP is to ____.
first messenger, second messenger
Nodes of Ranvier
gaps in the myelin of axons
The anterior pituitary is composed of ____ and the posterior pituitary is composed of ____
glandular tissue; neural tissue
EPSP
graded depolarization
Inhibitory synapses on a neuron
hyperpolarize the postsynaptic cell
most important consideration in developing a drug that will act in the brain
if the drug will cross the blood-brain barrier
Vesicles are located
in presynaptic terminals
Many dendrites contain short outgrowths called spines that
increase the surface area available for synapses
Nitric oxide
increases blood flow to certain areas of the brain
Saltatory conduction ____ the velocity of action potentials and ____ the amount of energy used by the neuron.
increases; decreases
psychophysiologist
interested in changes in heart rate
Chemicals are released by axons
into the junction between neurons
A receptor can directly open a channel exerting a(n) ____ effect or it can produce slower but longer ____ effects.
ionotropic; metabotropic
oligodendrocytes
myelinate axons in the brain and spinal cord
resting potential is mainly the result of
negatively charged proteins inside the cell
At the microscopic level, we find two kinds of cells
neurons and glia
Santiago Ramon y Cajal
neurons are separate from one another.
inhibitory synapses in the spinal cord
ordinarily prevents extensor muscles from contracting at the same time as flexor muscles
Increased permeability to which of the following ions would most likely result in an IPSP?
potassium
Small, charged molecules can cross the cell membrane through
protein channels
At the peak of the action potential, the electrical gradient of potassium:
pushes potassium out of the cell
Temporal summation most likely occurs with
rapid succession of subthreshold excitation.
Ionotropic effects
rapid, short-lived effects
"spontaneous firing rate"
rate of producing action potentials even when it is not stimulated.
After a meal that was rich in the amino acid tryptophan, which neurotransmitter level would be increased the most
serotonin
In general, a single neuron releases ____ neurotransmitter(s) and can respond to ____ neurotransmitter(s)
several; many
One of the most distinctive features of neurons compared to other types of cells
shape
During the entire course of events from the start of an action potential until the membrane returns to its resting potential, what is the net movement of ions?
sodium in, potassium out
EPSP results from
sodium ions entering the cell.
What does myelin cover
some axons in vertebrates and none in invertebrates
Synapses
specialized junctions between neurons
presynaptic terminal
stores high concentrations of neurotransmitter molecules in vesicles
What provides the building blocks for synthesizing all neurotransmitters
substances found in the diet
Ribosomes
synthesizes new proteins
Reuptake
the absorption of neurotransmitters by the presynaptic neuron
advantage of having a resting potential
the cell is prepared to respond quickly to a stimulus
resting potential
the difference in voltage called that typically exists between the inside and the outside of a neuron
Charles S. Sherrington
the first to infer the properties of synapses
Concentration gradients lead to
the movement of ions to areas of their lowest concentrations
What causes an EPSP
the opening of sodium channels
relative refractory period
the sodium gates are reverting to their usual state
at the peak of the action potential
the sodium gates begin to close, shutting out further entry of sodium into the cell
Sherrington deduced that transmission at a synapse must be slower than conduction along an axon. This was based on what kind of evidence
the speed of reflexive responses
two requirements for the brain to metabolize glucose
thiamine and oxygen
The sodium-potassium pump repeatedly transports ____ sodium ions out of the cell while drawing ____ potassium ions into it.
three; two
Which of the following is NOT a factor in determining whether or not two EPSPs combine to reach threshold
threshold of the presynaptic cell
Temporal summation is to ____ as spatial summation is to ____
time, location
NOT performed by glia
transmitting information
The risk of having part of the brain unprotected by the blood-brain barrier
viruses or toxic chemicals are more likely to damage it
Which chemicals flow most freely across a cell membrane
water, oxygen, and carbon dioxide
evolutionary explanation of why we get goose bumps when cold
we inherited the mechanism from our remote ancestors who had more hair.
