Biopsych Vocabulary Flashcards
Dualism
The belief that the body is physical but the mind (or soul) is not
Monism
The belief that the world consists only of matter and energy and that the mind is a phenomenon produced by the workings of the nervous system
Blindsight
The ability of a person who cannot see objects in his or her blind field to accurately reach for them while remaining unconscious of perceiving them
Caused by damage to the “mammalian” visual system of the brain
Corpus callosum
The largest commissure of the brain, interconnecting the areas of neocortex on each side of the brain
Split-brain operation
Brain surgery that is occasionally performed to treat a form of epilepsy; the surgeon cuts the corpus callosum, which connects the two hemispheres of the brain.
Cerebral hemispheres
The two symmetrical halves of the brain
Unilateral neglect
A syndrome in which people ignore objects located toward their left and the left sides of objects located anywhere; most often caused by damage to the right parietal lobe
Generalization
A type of scientific explanation; a general conclusion based on many observations of similar phenomenon
Reduction
A type of scientific explanation; a phenomenon is described in terms of the more elementary processes that underlie it
Reflex
An automatic, stereotyped movement that is produced as the direct result of a stimulus
Model
A mathematical or physical analogy for a physiological process
Doctrine of specific nerve energies
Muller’s conclusion that because all nerve fibers carry the same type of message sensory information must be specified by the particular nerve fibers that are active
Experimental ablation
The research method in which the function of a part of the brain is inferred by observing the behaviors an animal can no longer perform after that part is damaged
Functionalism
The principle that the best way to understand a biological phenomenon is to try to understand its useful functions for the organism
Natural selection
The process by which inherited traits that confer a selective advantage become more prevalent in a population.
Mutation
A change in the genetic information contained in the chromosomes of sperm or eggs which can be passed on to an organism’s offspring; provide genetic variability
Selective advantage
A characteristic of an organism that permits it to produce more than the average number of offspring of its species
Evolution
A gradual change in the structure and physiology of plant and animal species– generally producing more complex organisms–as a result of natural selection
Neoteny
A slowing of the process of maturation, allowing more time for growth; an important factor in the development of large brains
Behavioral neuroscientists
A scientist who studies the physiology of behavior, primarily by performing physiological and behavioral experiments with lab animals.
Sensory neurons
Neurons that detect changes in the external or internal environment and sends information about these changes to the central nervous system
Motor neuron
A neuron located within the central nervous system that controls the contraction of a muscle or the secretion of a gland
Interneuron
A neuron located entirely within the central nervous system
Central nervous system
The brain and spinal cord
Peripheral nervous system
The part of the nervous system outside the brain and spinal cord, including the nerves attached to the brain and spinal cord.
Soma
Cell body of a neuron which contains the nucleus
Dendrite
A branched, treelike structure attached to the soma of a neuron; receives information from the terminal buttons of other neurons
Synapse
A junction between the terminal button of an axon and the membrane of another neuron
Axon
The long, thin, cylindrical structure that conveys information from the soma of a neuron to its terminal buttons
Multipolar neuron
A neuron with one axon and many dendrites attached to its soma
Bipolar neuron
A neuron with one axon and one dendrite attached to its soma
Unipolar neuron
A neuron with one axon attached to its soma; the axon divides with one branch receiving sensory information and the other sending the information into the central nervous system
Terminal button
The bud at the end of an axon; forms synapses with another neuron; sends information to the neuron
neurotransmitter
A chemical that is released by a terminal button; has an excitatory or inhibitory effect on another neuron
membrane
A structure consisting principally of lipid molecules that defines the outer boundaries of a cell and also constitutes many of the cell organelles, such as the Golgi apparatus
nucleus
A structure in the central region of a cell, containing the nucleolus and chromosomes
Nucleolus
A structure within the nucleus of a cell that produces ribosomes
ribosome
A cytoplasmic structure, made of protein, that serves as the site of production of proteins translated from mRNA
chromosome
A strand of DNA, with associated proteins, found in the nucleus; carries genetic information
deoxyribonucleic acid (DNA)
a long, complex macromolecule consisting of two interconnected helical strands; along with associated proteins, strands of DNA constitute the chromosomes
gene
functional unit of the chromosome, which directs synthesis of one or more proteins
messenger ribonucleic acid (mRNA)
a macromolecule that delivers genetic information concerning the synthesis of a protein from a portion of a chromosome to a ribosome
enzyme
molecule that controls a chemical reaction, combining two substances or breaking a substance into two parts
non-coding RNA (ncRNA)
form of RNA that does not encode for protein but has functions of its own
cytoplasm
viscous, semiliquid substance contained in the interior of a cell
mitochondrion
organelle that is responsible for extracting energy from nutrients
adenosine triphosphate (ATP)
molecule of prime importance to cellular energy metabolism; its breakdown liberates energy
endoplasmic reticulum
parallel layers of membrane found within the cytoplasm of a cell. Rough endoplasmic reticulum contains ribosomes and is involved with production of proteins that are secreted by the cell. Smooth endoplasmic reticulum is the site of synthesis of lips and provides channels for the segregation of molecules involved in various cellular processes
Golgi apparatus
complex of parallel membranes in the cytoplasm that wraps the products of a secretory cell
exocytosis
secretion of a substance by a cell through means of vesicles; the process by which neurotransmitters are secreted
lyosome
organelle surrounded by membrane; contains enzymes that break down waste products
cytoskeleton
formed of microtubules and other protein fibers, linked to each other and forming a cohesive mass that gives a cell its shape
microtubule
long strand of bundles of protein filaments arranged around a hollow core; part of the cytoskeleton and involved in transporting substances from place to place within the cell
axoplasmic transport
an active process by which substances are propelled along microtubules that run the length of the axon
anterograde
in a direction along an axon from the cell body toward the terminal buttons
retrograd
in a direction along an axon from the terminal buttons toward the cell body
glia
supporting cells of the central nervous system
astrocyte
a glial cell that provides support for neurons of the central nervous system, provides nutrients and other substances and regulates the chemical composition of the extracellular fluid
phagocytosis
process by which cells engulf and digest other cells or debris caused by cellular degeneration
oligodendrocyte
a type of glial cell in the central nervous system that forms myelin sheaths
myelin sheath
a sheath that surrounds axons and insulates them, preventing messages from spreading between adjacent axons
node of Ranvier (raw vee ay)
a naked portion of a myelinated axon between adjacent oligodendroglia or Schwann cells
microglia
smallest of glia cells; act as phagocytes and protect the brain from invading microorganisms
Schwann cell
a cell in the peripheral nervous system that is wrapped around a myelinated axon, providing one segment of its myelin sheath
blood-brain barrier
a semipermeable barrier between the blood and the brain produced by the cells in the walls of the brain’s capillaries
area postrema (poss tree ma)
a region of the medulla where the blood-brain barrier is weak; poisons can be detected there and can initiate vomiting
electrode
a conductive medium that can be used to apply electrical stimulation or to record electrical potentials
microelectrode
a very fine electrode, generally used to record activity of individual neurons
membrane potential
the electrical charge across a cell membrane; the difference in electrical potential inside and outside the cell
oscilloscope
a laboratory instrument that is capable of displaying a graph of voltage as a function of time on the face of a cathode ray tube
resting potential
the membrane potential of a neuron when it is not being altered by excitatory or inhibitory postsynaptic potentials; approximately -70mV in the giant squid axon
depolarization
reduction (toward zero) of the membrane potential of a cell from its normal resting potential
hyperpolarization
an increase in the membrane potential of a cell, relative to the normal resting potential
action potential
the brief electrical impulse that provides the basis for conduction of information along an axon
threshold of excitation
the value of the membrane potential that must be reached to produce an action potential
diffusion
movement of molecules from regions of high concentration to regions of low concentration
electrolyte
an aqueous solution of a material that ionizes– namely, a soluble acid, base, or salt
ion
a charged molecule.
cations
positively charged molecules
anions
negatively charged molecules
electrostaticc pressure
attractive force between atomic particles charged with opposite signs or the repulsive force between atomic particles charged with the same sign
intracellular fluid
fluid contained within a cell
extracellular fluid
body fluids located outside of the cells
sodium-potassium transporter
a protein found in the membrane of all cells that extrudes sodium ions from and transports potassium ions into the cell
ion channel
a specialized protein molecule that permits specific ions to enter or leave cells
voltage-dependent ion channel
an ion channel that opens or closes according to the value of the membrane potential
all-or-none law
principle that once an action potential is triggered in an axon, it is propagated, without decrement, to the end of the fiber
rate law
the principle that variations in the intensity of a stimulus or other information being transmitted in an axon are represented by variations in the rate at which the axon fire
salatory conduction
conduction of action potentials by myelinated axons. The action potential appears to jump from one node of Ranvier to the next
postsynaptic potential
alterations in the membrane potential of a postsynaptic neuron, produced by liberation of neurotransmitter at the synapse
binding site
location on a receptor protein to which a ligand binds
ligand
a chemical that binds with the binding site of a receptor
dendritic spine
a small bud on the surface of a dendrite with whicch a terminal button of another neuron forms a synapse
presynaptic membrane
membrane of a terminal button that lies adjacent to the postsynaptic membrane and through which the neurotransmitter is released
postsynaptic membrane
cell membrane opposite the terminal button in a synapse; the membrane of the cell that receives the message
synaptic cleft
the space between the presynaptic membrane and the postsynaptic membrane
synaptic vesicle
a small, hollow, beadlike structure found in terminale buttons; contains molecules of a neurotransmitter
release zone
a region of the interior of the presynaptic membrane of a synapse to which synaptic vesicles attach and release their neurotransmitter into the synaptic cleft.
postsynaptic receptor
receptor molecule in the postsynaptic membrane of a synapse that ccocntains a binding site for a neurotransmitter
neurotransmitter-dependent ion channel
an ion channel that opens when a molecule of a neurotransmitter binds with a postsynaptic receptor
ionotropic receptor
a receptor that contains a binding site for a neurotransmitter and an ion channel that opens when a molecule of the neurotransmitter attaches to the binding site
metabotropic receptor
a receptor that contains a binding site for a neurotransmitter; activates an enzyme that begins a series of events that opens an ion channel elsewhere in the membrane of the cell when a molecule of the neurotransmitter attaches to the binding site
G protein
a protein coupled to a metabotropic receptor. conveys messages to other molecules when a ligand binds with and activates the receptor
second messenger
a chemical produced when a G protein activates an enzyme; carries a signal that results in the opening of the ion channel or causes other events to occur in the cell
excitatory postsynaptic potential (EPSP)
an excitatory depolarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button
inhibitory postsynaptic potential (IPSP)
an inhibitory hyperpolarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button
