Unit #10 Cells of the Nervous System
Perikaryon
Cell body of neuron.
Schwann Cells
Cells found in peripheral nervous system responsible for producing the myelin sheath. They electrically insulate axons and speed up the electrical impulse as it travels through the axon.
Astrocytes
Cells found in the central nervous system responsible for attaching neurons to capillaries, protecting them from harmful substances found in the blood. These cells also produce scar tissue.
Ependymal Cells
Cells found in the central nervous system that are responsible for producing cerebralspinal fluid.
Oligodencrocytes
Cells found in the central nervous system that are responsible for producing the myelin sheath. They electrically insulate axons and speed up the electrical impulse as it travels through the axon.
Microglia
Cells found in the central nervous system that are responsible for protecting the brain and spinal cord from infections.
Neurons
Cells of the nervous system that send information to and from the brain and spinal cord.
Nerve
Concentration of axons of neurons in teh peripheral nervous system.
Tract
Concentration of axons of neurons in the central nervous system.
Nucleus
Concentration of cell bodies of neurons in the central nervous system.
Ganglion
Concentration of cell bodies of neurons in the peripheral nervous system.
Myelin Sheath
Fatty wrapping around axons formed by Schwann cells and Oligodendrocytes.
Synapse
Gap that exists between two adjacent neurons, or a neuron and an effector organ.
Nodes of Ranvier
Gaps that exist between adjacent Schwann cells,which speed up the transmission of electrical impulses as they travel through the axon.
Glial Cells
Group of cells responsible for taking care of high maintenance neurons. Types of cells in this category include Schwann cells, Oligodendrocytes, Microglial, Ependymal, and Astrocytes.
Centrioles
Organelle NOT found in neurons. This is the reason why neurons cannot replicate.
Nissl substance
Organelle formed from rough endoplasmic reticulum, which means that it contains ribosomes that make protein. This organelle is responsible for repairing damaged axons.
Dendrite
Portion of neuron responsible for receiving information from sense organs or other neurons.
Axon
Portion of neuron responsible for sending information to effector organs or other neurons.
Neurofibrils
Proteins that make up the cytoskeleton of a neuron.
Reflex Arc
Receptor - Sensory pathway - Integration center - Motor pathway - Effector organ
Neurolemma
The outermost layer of a Schwann cell that contains cytoplasm and the nucleus.