Chapter 0: Foundations of Biopsychology - Cells of the Nervous System Flashcards
The nervous system is made up of two (2) types of cells, which are?
- Neurons
- Glia
Is specialized to carry out the functions of information processing and communication.
Neuron.
Cells in the nervous system that support the activities of neurons.
Glia.
A small structure within a cell that carries out a specific function.
Organelle.
The main mass of a neuron, containing the nucleus and many organelles.
Cell body / soma.
The branch of a neuron usually responsible for carrying signals to other neurons.
Axon.
The branch of a neuron that generally receives information from other neurons.
Dendrite.
Its primary task is to form a boundary between the cell and its external environment.
Neuron membrane (cell membrane).
Separates the intracellular fluid of the cell’s interior from the extracellular fluid surrounding the neutron.
Neural membrane.
Neural membranes consist of?
Double layers of phospholipid molecules.
Embedded within the lipid layers are ________ that serve as ion channels and ion pumps.
Proteins.
A protein structure embedded in a cell membrane that allows ions to pass without the use of additional energy.
Ion channel.
A protein structure embedded in a cell membrane that uses energy to move ions across the membrane.
Ion pump.
These open and close in response to the electrical status of adjacent areas of membrane.
Voltage-dependent channels.
An ion channel in the neural membrane that responds to chemical messengers.
Ligand-gated channel.
An ion pump that uses energy to transfer three (3) sodium ions to the extracellular fluid for every two potassium ions retrieved from the extracellular fluid.
Sodium-potassium pump.
A protein structure embedded in the neural membrane that uses energy to move calcium ions out of the cell.
Calcium pump.
These help to maintain the differences in chemical composition between the intracellular and extracellular fluids.
Sodium-potassium and calcium pumps.
The structural support that maintains the shape of the neuron is provided by the?
Cytoskeleton.
The largest fiber in the cell cytoskeleton, responsible for the transport of neurotransmitters and other products to and from the cell body.
Microtubule.
These run parallel to the length of the axon and provide structural support.
Neurofilaments.
The smallest fiber found in the cell cytoskeleton that may participate in the changing of the length and shape of axons and dendrites.
Microfilament.
The substructure within a cell body that contains the cell’s DNA.
Nucleus.
An organelle in the cell body involved with protein synthesis.
Ribosome.
An organelle in the cell body that participates in protein synthesis.
Endoplasmic reticulum.
An organelle in the cell body that packages protein in vesicles.
Golgi apparatus.
Organelles that provide energy to the cell.
Mitochondria.
These produce and assemble the cell’s ribosomes.
Nucleolus.
Specialized for the generation of action potentials.
Axon hillock.
The fatty insulating material covering some axons that boosts the speed and efficiency of electrical signaling.
Myelin.
The uncovered section of axon membrane between two adjacent segments of myelin.
Node of Ranvier.
One of the branches near the end of the axon closest to its targets.
Collateral.
The swelling at the tip of an axon collateral specialized for the release of neurotransmitter substances.
Axon terminal.
A neuron with one branch that extends a short distance from the cell body then splits into two branches.
Unipolar neuron.
A neuron with two branches: one axon and one dendrite.
Bipolar neuron.
A neuron that has multiple branches, usually one axon and numerous dendrites.
Multipolar neuron.
The largest varieties of glial cells.
Macroglia.
The smaller varieties of glial cells.
Microglia.
A type of glial cell found in the central nervous system whose functions include providing structural and nutritional support for neurons, isolation of the synapse, debris cleanup, blood-brain barrier, and participation in chemical signaling.
Astrocyte.
A type of glial cell found in the central nervous system whose function is for the myelination of axons.
Oligodendrocyte.
A type of glial cell found in the peripheral nervous system whose function is for the myelination of axons
Schwann cell.
A type of glial cell found in the central nervous system whose function is for debris cleanup.
Microglia.
This is characterized by a large concentrations of sodium and chloride ions and a relatively small concentration of potassium ions.
Extracellular fluid.
The measurement of the electrical charge across the neural membrane when the cell is not processing information.
Resting potential.
The force that moves molecules from areas of high concentration to areas of low concentration (also through electrical force).
Diffusion.
The threshold for action potential is equal to?
-65mV
The human brain contains about what number of neurons?
100 billion.
The average neuron forms about how many synapses?
1000.
A type of synapse in which messages are transmitted from one neuron to another by chemical neurotransmitters.
Chemical synapse.
A type of synapse in which a neuron directly affects an adjacent neuron through the movement of ions from one cell to the other.
Electrical synapse.
The width of the synaptic gap in an electrical synapse is equal to?
3.5mm.
The width of the synaptic gap in a chemical synapse is equal to?
20mm.
The type of message that can travel across an electrical synapse.
Excitatory only.
The type of message that can travel across a chemical synapse.
Excitatory or inhibitory.
The process in which vesicles fuse with the membrane of the axon terminal and release neurotransmitter molecules into the synaptic gap.
Exocytosis.
A special protein structure embedded in neural membrane that responds to chemical messengers.
Receptor site.
Three (3) methods for deactivating neurotransmitters.
- Diffusion away from the synapse
- Through the action of special enzymes
- Through reuptake
The presynaptic membrane uses its own set of receptors known as ____________ to recapture molecules of neurotransmitter substance and return them to the interior of the axon terminal.
Transporters.
