page. 116-130 Flashcards
Biologists consider it the most highly organized unit of any form of life.
the nervous system
includes the brain and the spinal cord, which are both encased in bone for protection.
central nervous system
protected by the cranium, is the principal organ of the nervous system
brain
the brain communicates with most of the body through the….
A thick bundle of nerve fibers located within the spinal cavity
spinal cord
The spinal cord and brain are covered by a triple layer
of protective tissues known as the
meninges
the meninges
The meninges are composed of an outer layer called the dura mater [d‚rÆè m¡Ætèr], a middle layer called the arachnoid [è¶rÅkÆnoidæ] mater, and an inner layer called the pia [p£Æè] mater. The dura mater, which is one of the strongest tissues of the body, serves primarily as a flexible protective layer. The arachnoid mater is composed of thin fibers, like the fibers of a spider’s web, that form an intricate three dimensional network around the brain
which support and insulate nerve tissue
glial cells
the actual nerve cells
neurons
is a short, branched extension of the cell that receives nerve impulses from other neurons and conducts them toward the cell body
dendrite
found within the brain and spinal
cord consists largely of the cell bodies of neurons and is gray because the cell bodies lack the white, specialized covering known as myelin
gray matter
is composed of axons and glial cells that are white because of their myelin content.
white matter
what are masses of cell bodies
ganglia
a network of interconnected nerve fibers going to or from a region
plexus
located at the back of the neck and shoulder, branches to form the median nerve and other arm nerves
Brachial plexus
a group of cell bodies in the brain or spinal cord are known as
nerve center
brain stem control your breathing
medulla oblongata
Neurons that transmit information to the central nervous system from the senses of sight, hearing, taste, touch, and smell, as well as those that transmit pain signals, are
sensory neurons
Neurons that relay signals from the central nervous system to the other parts of the body are the
motor neurons
found only in the central nervous system, relay signals between neurons or groups of neurons and are responsible for the processing of information by the brain, like the logic circuits of a computer
interneurons
These tightly sealed capillary walls, that protect the central nervous system from being permanently damaged every time you get sick are called
blood-brain barrier
Your brain contains its own white blood cells, which help protect the brain from infection
microglia
When invading microorganisms enter the nerve tissue and infect the meninges, they can cause a disease called
meningitis
serious disease
that attacks the spinal cord that is caused by a virus that enters the motor neutrons of the spinal cord
poliomyelitis or polio