Nerve Tissue Flashcards
(32 cards)
What is the CNS?
BRain and Spinal cord
WHat is PNS?
nerves that extend from the CNS into the periphery
What does afferent mean?
Sensory input
What does efferent mean?
Motor output
Ganglia
clusters of neuoronal cell bodies in the PNS
-in CNS they can be referred to as nuclei
What are the two types of cells in nerve tissue?
neurons and supporting cells neuroglia
What are the two parts of the neuron?
the cell body (soma) and cell processes
what is neuroglia?
neuron supporting cells
What is larger, the neuron or its surrounding glial cells?
the neuron
What does the cell body do?
processes electrical info
what are the large clusters of the rER that take are basophilic?
Nissl bodies
What do dendrites do?
Carry electrical signals toward the nerve cell body
What does an axon do?
Carries electrical signals away from the nerve cell body
What is the synapse?
where electrical signals are transferred from the axon terminal of the nerve to an effector cell
How are neurons classified?
based on the relationship between the nerve cell body, dendrites, and the axon
What are the four classes of neurons?
- Anaxonic: no distinct axon
- Multipolar: many dendrites
- Bipolar: One dendrite and one axon
- Unipolar: one cell process from which branches a single axon and single dendrite
What are the different functional classifications of neurons?
- Sensory (afferent): carry signals into CNS, most unipolar
- Motor (efferent): Carry signals away from CNS, most multipolar
- Interneuron: found bw sensory and motor neurons and are located in the CNS. make up most of the neurons found in the CNS
What are the different kinds of Glial cells?
In the CNS -Oligodendrocytes -Microglial -Astrocytes -Ependymal cells In the PNS -Satellite -Schwann
What are Oligodendrocytes?
have processes that form myelin sheaths around CNS nerve fibers
What are ependymal cells?
cuboidal-like epithelia cells
- have both cilia and microvilli
- line cerebrospinal fluid-filled cavities
What is the CSF?
cerebrospinal fluid
-forms as a filtrate of the blood
Satellite cells?
surrounds the cell body of a neuron
Schwann cells
form myelin
surround neurons in the PNS
What is the myelin sheath made out of in the PNS and the CNS
Schwann cells in PNS
Oligodendrocytes in CNS