Chapter 11 nervous system

How does the composition of gray matter differ from white matter

Gray matter is a group of cell bodies and U myelinated fibers and white matter is composed of myelinated fibers

Neurons

Have extreme longevity and can last for a lifetime. Are Amiotic and lose ability to divide and don't replace if destroyed. High metabolic rate and require oxygen and glucose and cannot survive without a few minutes without oxygen

How does the myelin sheath of a neuron effect the speed of an impulse

Increases speed of the impulse because action potential leap from one node to the next

How does a tract differ from a nerve

Tract is a bundle of nerve fibers found in the CNS and nerve is a bundle of fibers found in PNS

Axon terminal

Communicate with other cell and sends impulses

Schwann cell

A type of supporting cell in the PNS; forms myelin sheaths and is vital to peripheral nerve fiber regeneration; forms myelin sheath

The principal way neurons communicate is by generating and propagating

Action potential/nerve impulses

Cell body or soma

Consists of a transparent spherical Nucleus surrounded by cytoplasm; major biosynthetic of a cell

Nucleus

Control center of a cell constrains genetic material

Glia cells that brace and anchor neurons to nutrient capillaries

Astrocytes

Glia cells that control the chemical environment around neurons, most importantly "mopping up" leaked potassium ions and recapturing released neurotransmitters

Astrocytes

Which glial cell is most abundant and versatile of the glial cells

Astrocytes

Which glial cells are found within CNS

Astrocytes, microglia, ependymal cells and oligodendrocytes

What is a reflex

Automatic reaction to a stimulation

How does the size of an axon affect the speed of an impulse

Bigger the fiber the faster the impulse

What is the function of the neurotransmitter known as acetylcholine

Bonds to receptor cites

Dendrite

Branching neuron process that serves as a receptive or input, region; transmits the nerve impulse toward the cell body

Which glial cell line the central cavities of the brain and spinal cord and the beating of their flagella circulates the cerebrospinal fluid that cushions the brain and spinal cord

Ependymal cells

Myelin sheath or neurilemma

Fatty insulating sheath that surrounds all but the smallest nerve fibers

What is a synapse

Functional junction or point of close contact between two neurons or between a neuron and an effector cell

Glia cells that serve to monitor health of nearby neurons and when dead neurons or microorganisms are present they transform into a special type of macrophage that phagocytizes microorganisms or neuronal debris

Microglia

Name two major types of cells that have an excitable membrane

Nerve cells and muscle cells

A transmitted action potential is also known as a

Nerve impulse

The other type of cell found in the nervous system is also called nerve cells

Neuron

Axon

Neuron process that carries impulses away from the nerve cell body; efferent process; the conduction portion of a nerve cell

The chemical substances that allow neurons to communicate with each other and send messages to The rest of the body as Called

Neurotransmitters

Glia cells that produce the myelin sheath around the nerve fibers in the CNS

Oligodendrocytes

What are the three major overlapping functions of the nervous system

Sensory input Inter junction or interneuron Motor output

Node of ranvier

Region that provides an impulse to leap

Vasodilation

Relaxation

Which glial cells are found within PNS

Satellite and Schwann cells

Glia cells that surround neuron with ganglia, but their function is still largely unknown

Satellite cells

Which glial cell form the myelin sheath around the larger nerve cells in the PNS

Schwann cells

Explain how nodes of ranvier form along an axon in the peripheral nervous system

Schwann cells wrap around axon and leaves a space between Schwann cells which is a node

Explain how sensory, motor, and interneurons differ functionally

Sensory carries impulses to CNS Motor go from neuron

Explain how an antihistamine might aid you when you have allergies

Stop active histamine

In the field of medicine does a neurologist specialize

Study of nervous system functions and its disorders

Long distance running is associated with the release of the neurotransmitters called endorphins explain why a long distance runner might experience what is called a runners high

There are natural opiate substance that inhibits pain and this mimicks the effect of morphine, heroine and meth