ch 8 Flashcards
principle organ of nervous system
brain
the part of the skull that provides a protective helmet for the brain
cranium
a thick bundle of nerve fibers located within the spinal cavity
spinal cord
transmit nerve signals to and from the rest of the body
spinal nerves
triple layer of protective tissues (around brain and spinal cord)
Meninges
branch directly from the brain stem and transmit nerve signals to and from the eyes, ears, mouth, face, and scalp
cranial nerves
one of the strongest tissues of the body, serves primarily as a flexible protective layer
Dura mater
composed of thin fibers that form an intricate three dimensional network around the brain
Arachnoid mater
forms a delicate covering that rests directly against the brain and spinal cord
pia mater
act as insulation
Glial cells
the nerve cells themselves
Neurons
contains a nucleus and most of the nerve cell’s cytoplasm
Cell body
a short, branched extension of the cell that receives nerve impulses from other neurons and conducts them toward the cell body
Dendrite
a long extension that relays nerve impulses from the cell body to other neurons.
Axon
lack myelin
Gray matter
white, specialized covering
myelin
composed of axons and glial cells that are white because of their myelin content (contain myelin)
White matter
masses of cell bodies
Ganglia
a network of interconnected nerve fibers going to or from a region
Plexus
branches to form the median nerve and other arm nerves
Brachial plexus
A group of cell bodies in the brain or spinal cord
Nerve center
Neurons that transmit information to the central nervous system from the senses of sight, hearing, taste, touch, and smell
Sensory neurons
Neurons that relay signals from the central nervous system to the other parts of the body; control muscles
Motor neurons
the go between/link for sensory and motor neurons
Interneurons
tightly sealed capillary walls
Blood brain barrier
infection in meninges
Meningitis
period of long unconsciousness
coma
A serious disease
that attacks the spinal cord
Polio
consists of nerves
Peripheral nervous system
bundles of nerve fibers branching from the brain and spinal cord
Nerves