Nervous System Flashcards
What is an arachnoid?
Where is it located?
Cerebrospinal fluid-filled space, contains spider web like filaments (meninges)
Located between dura matter and pia matter
What is the brain stem?
What is it connected to?
Contains centers that control breathing, cardiac function, and digestive tract function
Connected to the spinal cord
What is the central nervous system made of?
Brain and spinal cord
What does the cerebellum do?
Coordinates movement, balance, posture, and complex reflexes
What does the cerebrum do?
Responsible for learning, intelligence, receiving, and interpreting sensory information
(Where the conscious mind resides)
What is the corpus callosum?
Made up of nerve fibers that connect right and left cerebral hemispheres
What are cranial nerves?
12 pairs of nerves that originate directly from the brain
What is the diencephalon?
Passageway between the brain stem and cerebrum
More of an area, not a specific thing
What is the dorsal horn of the spinal cord?
Portion of gray matter of spinal cord that conducts sensory impulses to brain
What is dura mater?
Outermost, thickest, and toughest layer of meninges
What are facial nerves?
Controls facial muscles and relays sensations from taste buds on tongue, carries nerve fibers to tear and salivary glands
What is the femoral nerve?
Motor function to muscles of thigh and carries sensory impulses from skin of hip, thigh, leg, and knee
What is gray matter?
Contains most of neuron cell bodies and is where any nerve impulses are initiated
What is gyrus?
Folds in the cerebrum and cerebellum
What is the hypothalamus?
Bridge between nervous system and endocrine system
Located between thalamus and pituitary glads
What is the median nerve?
Runs to elbow and forearm region
What are meninges?
Covers brain and spinal cord
Has three layers
What is a mixed nerve?
Contains both sensory and nervous fibers
What is a motor nerve?
Carries messages away from brain to the rest of the body
What is a neuron?
Nerve cell.
Basic functional unit of nervous system
What is the peripheral nervous system?
Made of cord-like nerves that originate from brain or spinal cords
What is pia mater?
Innermost layer of meninges
Very thin- tightly adheres to surface of brain and spinal cords
What is the radial nerve?
Supplies motor impulses to muscles of elbow, carpus, and digits, carries sensory impulses to the brain
What a sciatic nerve?
Carries motor impulses to flexor muscle of stifle joint digits and flexor muscles of the hock
What are sensory nerves?
Nerves that carry messages to the brain
What the spinal cord?
Continuation of brain stem
Conducts sensory information and motor instructions between the brain and periphery of the body
Where are spinal nerves?
Originate from the spinal cord
What is sulcus?
Shallow fissures that separate guri in the brain
What is the thalamus?
Relay station
Regulating sensory inputs to cerebrum
What is the ulnar nerve?
Carries sensory nerve impulses to the brain from foot pads
“Funny bone”
What is the vagus nerve?
Carries motor impulses from pharynx, larynx, trachea, esophagus, ect.
Longest nerve in body
What does the ventral horn of spinal cord do?
Conducts motor impulses away from the brain
What is white matter?
“Wiring” that carries impulses in and out of gray matter
Found in medulla (inner portion) of cerebrum an cerebellum
True or False:
Nerves have an all or nothing impulse.
True
What is the resting state?
The cell has potential energy but is not yet being used
(Active rest)
Has to work to stay resting
Cell membranes of neurons are _________ at rest.
Electrically polarized
What is the sodium-potassium pump?
Higher concentration of sodium on the outside, higher concentration of potassium on the inside
The cell becomes polarized/ Creates poles
What is resting membrane potential?
Electrical difference in charges across the membrane
What is the net, negative resting membrane potential?
-70mV (within the cell)
Characteristics of depolarization
Sodium channel will pop open and fly in the cell
Charge is changing
Does not need energy
Sodium influx results in loss of two distinct poles of Na and K on either side of membrane
Sodium driven into cell by concentration gradient
What happens when the cell loses its two distinct poles of Na and K?
Cell becomes neutral
What is action potential?
Significant change in electrical charge from negative to positive
What is repolarization?
Opening of potassium pump
Potassium ions passively diffuse out of the cell, motivated by concentration gradia
Ions have flipped (K on outside, Na on inside)
Need ATP to get on right sides
Which is stronger, potassium or sodium?
Sodium
What needs to happen before the cell can “fire”?
Has to reach a certain threshold
Explain the wave of depolarization
Waves of sodium channels opening to allow sodium influx
Conduction down neuron
Action potential would be generated and conducted along entire neuron
(Can be called action potential/nerve impulse/Wave of depolarization)
What is the refractory period?
“Insensitive” to new stimuli until it recovers from previous nerve impulses
What is the relative refractory period?
Cell is still refractory to stimuli of normal intensity
What is the resting potential for all animals?
-55mV
What is synapse?
The gap between neurons
