NERVOUS SYSTEM - set A
What are the three functions of the nervous system?
- It monitors changes (sensory output), process and interprets (Integration), and causes a response or effect (motor output)
These type of glial cells monitor the health of nearby neurons, scavenge pathogens and dead cells.
- Microglial cells
A whitish, fatty material with a waxy appearance that insulate and protect the fibers and increases the nerve transmission rate of nerve impulses
- Myelin sheath
It is the master control and communication system of the body that uses electrical impulses for communication
- Nervous system
2 types of cells that made up the nervous tissue
- Glial cells/neuroglia and neurons
What is a synapse?
- It is an impulse transmitted from one neuron to another.
These type of glial cells produce cerebrospinal fluid that cushions the neurons. These lines the central cavities of the brain and the spinal cord.
- Ependymal cells
What is a synaptic cleft?
- A gap that separates the axon terminal to another neuron or target cell
What is a dendrite?
- A part of a neuron that conveys incoming messages towards the cell body.
What is an axon?
- A part of a neuron that generates nerve impulses, and conduct them away from the cell body.
These type of glial cells provide nutrients to neurons, maintain their extracellular environment, and provide structural support. (most abundant)
- Astrocytes
What are the types of glial cells in the mature CNS?
- Astrocytes (star-shaped), oligodendrocytes, ependymal and microglial cells (spiderlike)
It is the cone-like region from the cell body.
- Axon hillock
It is the metabolic center of the neuron.
- Cell body
What are neurons?
- Cells that transmit messages from one part of the body to another.
Cytoplasm of a nerve cell does have centrioles.
- False
the outermost nucleated cytoplasmic layer of Schwann cells (also called neurilemmocytes) that surrounds the axon of the neuron. It forms the outermost layer of the nerve fiber in the peripheral nervous system.
- Neurilemma
These are responsible in maintaining the cell shape of a neuron.
- Nissl bodies (rough ER) and neurofibrils (intermediate filament)
It is the regular intervals of gaps or indentations, formed due to the many individuals Schwann cells.
- Nodes of Ranvier
These type of glial cells form the myelin sheath around axons.
- Oligodendrocytes
These cells form the myelin sheath around nerve fibers in the PNS
- Schwann cells
What are the parts of a neuron?
- The cell body, process or fibers, and myelin sheaths
Multiple sclerosis is a demyelinating disease affecting the central nervous system. What type of cell would be the most likely target of this disease? Why?
- The disease would target oligodendrocytes. In the CNS, oligodendrocytes provide the myelin for axons.
What are neurotransmitters?
- These are chemical messengers that transmit a message from a nerve cell across the synapse to a target cell. These are released once it reaches the axon terminals
What are glial cells/neuroglia?
- These are composed of cells that support, insulate, and protect the delicate neurons and do not transmit nerve impulse. These cells don't lose their ability to divide, this is why most brain tumors are formed from neuroglia.
It takes many Schwann cells to make a single myelin sheath; one oligodendrocyte can form many myelin sheaths in the CNS.
- True
These are the branches forming from the terminal end of axons.
Axon terminals
It acts as protective cushioning cells for peripheral neuron cell bodies
Satellite cells
What are the glial cells of the PNS?
Schwann cells and satellite cells