B2-Structure and Functions of Cells of the Nervous System Flashcards
Motor neuron
A neuron located within the central nervous system that controls the contraction of a muscle or the secretion of a gland
Sensory neuron
A neuron that detects change in the external or internal environmental and sends information about these changes to the central nervous system
Interneuron
A neuron located entirely within the central nervous system
Central nervous system (CNS)
The brain and spinal cord
Peripheral nervous system (PNS)
The part of the nervous system outside the brain and spinal cord, including the nerves attached to the brain and spinal cord
Soma
The 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 form 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 it soma; the axon divides with the one branch receiving sensory information and the other sending the information into the central nervous system
Terminal button
The bud at the end of a branch of an axon; forms synapses with another neuron send information to that 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
Cytoplasm
The viscous, semiliquid substance contained in the interior of a cell
Mitochondria
And organelle that is responsible for extracting energy from nutrients
Adenosine triphosphate (ATP)
A molecule of prime importance to cellular energy metabolism; it’s breakdown liberates energy
Nucleus
A structure in the central region of a cell, containing the chromosomes
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
The functional unit of the chromosome, which directs synthesis of one or more proteins
Cytoskeleton
Support structure formed of microtubules and other protein fibers that are linked to each other and form a cohesive mass that gives a cell it’s shape
Enzyme
A molecule that controls a chemical reaction, combining two substances or breaking a substance into two parts