Exam 3 (Nervous System) Flashcards
Central Nervous System (CNS)
brain and spinal cord
Peripheral Nervous System (PNS)
cranial nerves and spinal nerves
Sensory Division (afferent)
nerves that carry information TO the CNS
Motor Division (efferent)
nerve fibers that carry impulses AWAY from the CNS
Voluntary Nervous System (somatic)
carry info from the skin, skeletal muscles, and joints
Involuntary Nervous System (automonic)
controls smooth and cardiac muscles and glands, further divided into the sympathetic and parasympathetic nervous systems
Astrocytes
abundant, star-shaped cells, brace and anchor neurons to blood capillaries, determine permeability and exchanges between blood capillaries and neurons
Microglia
spider-like phagocytes, monitor health of nearby neurons, dispose of debris
Ependymal cells
lines cavities of the brain and spinal cord, cilia assist with circulation of cerebrospinal fluid
Oligodendrocytes
wrap around nerve fibers in the CNS, produce myelin sheaths
Schwann cells
form myelin sheath around nerve fibers in the PNS
Satellite cells
protect and cushion neuron cell bodies
Cell body
metabolic center of the neuron
Dendrites
conduct impulses TOWARD the cell body
Axons
conduct impulses away from the cell body
Axonal terminals
contain vesicles with neurotransmitters
Synaptic cleft (synapse)
gap between axon terminals and the next neuron, functional junction between nerves where a nerve impulse is transmitted
Myelin sheath
schwann cells wrap axons in a jelly roll-like fashion to form the myelin sheath
nodes of Ranvier
gaps in myelin sheath along the axon
gyri
ridges in the brain
sulci
grooves in the brain
basal ganglia
responsible for motor control
Thalamus
relay station for sensory impulse, transfers impulses to the correct part of the cortex
Hypothalamus
regulates body temp, water balance, metabolism; regulates the nearby pituitary gland
Epithalamus
houses the pinal body; includes the choroid plexus
Choroid plexus
forms spinal fluid
Midbrain
2 bulging fiber tracts, 4 rounded protrusions, are visual and auditory reflex centers
Pons
mostly composed of fiber tracts, includes nuclei involved in the control of breathing
Medulla oblongata
includes important fiber tracts; heart rate, blood pressure, breathing, swallowing, vomiting
Cerebellum
2 hemispheres, controls balance
Dura matter
outermost layer of brain, double-layered external covering
Arachnoid matter
middle layer of the brain, web-like extensions span the subarachnoid space to attach it to the pia mater
Pia mater
clings to the surface of the brain and spinal cord
Cerebrospinal Fluid (CSF)
CSF forms a watery cushion to protect the brain and spinal cord
Blood-brain barrier
allows water, glucose, and amino acids to pass through the capillary walls
Cauda equina
collection of spinal nerves at inferior end
Gray matter
surround the central canal, made up of cell bodies
White matter
3 regions (dorsal, lateral, ventral columns), composed of nerve fibers
Dorsal horns
house interneurons, receive info from sensory neurons in the dorsal root
Dorsal root ganglion
house cell bodies
Sensory tracts
conduct impulses toward brain
Motor tracts
carry impulses from brain to skeletal muscles
Cerebral areas involved in special senses
Occipital lobe: visual areas
Temporal lobe: auditory and olfactory areas
Olfactory nerve
sense of smell
Optic nerve
vision
Oculomotor nerve
eye muscle involuntary movements
Trochlear nerve
eye muscle voluntary movements
Trigeminal nerve
chew and facial sensation
Abducen nerve
eye movement
Facial nerve
expression and taste
Vestibulocochlear nerve
hearing and balance
Glossopharyngeal nerve
throat (gagging)
Vagus nerve
taste and tongue movement
Accessory nerve
move neck
Hypoglossial
tongue muscles
Sympathetic System
fight-or-flight
Parasympathetic System
rest-and-digest