Central Nervous System, the portion of the vertebrate nervous system consisting of the brain and spinal cord
the muscle cells or gland cells that actually carry out the body's responses to stimuli.
specialized region of the axon, which connects the inital segment of the axon to the cell body
a layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next
Ends of axons that form one side of the synaptic cleft; the location where neurotransmitters are stored.
Cell recieveing the neurotransmitter, so that sodium ions can go in and Action potenital may occur
A muscle cell or gland cell that performs the body's responses to stimuli; responds to signals from the brain or other processing center of the nervous system.
largest, most numerous glial cells; maintain blood-brain barrier to isolate CNS from general circulation; provide structural support for CNS; regulate ion and nutrient concentrations; perform repairs to stabilize tissue and prevent further injury
blood brain barrier
Blood vessels (capillaries) that selectively let certain substances enter the brain tissue and keep other substances out
Supporting cells of the peripheral nervous system responsible for the formation of myelin.
The charge difference between a cell's cytoplasm and the extracellular fluid, due to the differential distribution of ions. Membrane potential affects the activity of excitable cells and the transmembrane movement of all charged substances.
voltage gated ion channels
A specialized ion channel that opens or closes in response to changes in membrane potential
sodium rushes into neuron through membrane, potassium ruses out; results in a change in charge cell becomes less negative
The movement of the membrane potential of a cell away from rest potential in a more negative direction.
the electrical charge or potential difference at which an action potential will occur
(neurology) the time after a neuron fires or a muscle fiber contracts during which a stimulus will not evoke a response
Rapid transmission of a nerve impulse along an axon, resulting from the action potential jumping from one node of Ranvier to another, skipping the myelin-sheathed regions of membrane.
Excitatory postsynaptic potential; a slight depolarization of a postsynaptic cell, bringing the membrane potential of that cell closer to the threshold for an action potential.
Inhibitory postsynaptic potential; a slight hyperpolarization of the postysynaptic cell, moving the membrane potential of that cell further from threshold.
(physiology) the process whereby multiple stimuli can produce a response (in a muscle or nerve or other part) that one stimulus alone does not produce
a neurotransmitter that enables learning and memory and also triggers muscle contraction
Neurotransmitter derived from amino acids, and include catecholamines (dopamine, epinephrine & norepinephrine) & indolamines (histamine & serotonin)ä
adrenaline; activates a sympathetic nervous system by making the heart beat faster, stopping digestion, enlarging pupils, sending sugar into the bloodstream, preparing a blood clot faster
neurotransmitter that is involved in arousal and the fight-or-flight system (also mood, sleep, and learning)
a monoamine neurotransmitter found in the brain and essential for the normal functioning of the central nervous system
An amino acid; an important inhibitory neurotransmitter in the lower brain stem and spinal cord.
the two lower chambers of the heart, and they pump blood out to the lungs and body., series of interconnected cavities within the cerebral hemispheres and brainstem filled with cerebrospinal fluid
The narrow cavity in the center of the spinal cord that is continuous with the fluid-filled ventricles of the brain.
Brain and spinal cord tissue that appears gray with the naked eye; consists mainly of neuronal cell bodies (nuclei) and lacks myelinated axons.
of the PNS of made up of sensory, or afferent, neurons that convey information to the CNS from sensory receptors that monitor the external and internal environment.
autonomic nervous system
the part of the nervous system of vertebrates that controls involuntary actions of the smooth muscles and heart and glands
The branch of the autonomic nervous system that mobilizes the body's resources for emergencies.
The branch of the autonomic nervous system that generally conserves bodily resources.
top of the brain which includes the thalamus, hypothalamus, and cerebral cortex; responsible for emotional regulation, complex thought, memory aspect of personality
the layer of unmyelinated neurons (the gray matter) forming the cortex of the cerebrum
the middle division of brain responsible for hearing and sight; location where pain is registered; includes temporal lobe, occipital lobe, and most of the parietal lobe
a nerve network in the brainstem that plays an important role in controlling arousal
the "little brain" attached to the rear of the brainstem; it helps coordinate voluntary movement and balance
the brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla
a neural structure lying below the thalamus; directs eating, drinking, body temperature; helps govern the endocrine system via the pituitary gland, and is linked to emotion
The theory of aging that suggests that our cells are pre-programmed genetically to divide a specific number of times and then cells lose their ability to repair themselves
suprachaiasmatic nucleus, regulates circadian rhythyms
light=cortisol release (alert)
important centers for motor coordination, acting as switches for impulses from other motor systems.
the more recently evolved portions of the cortex of the brain that are involved with higher mental functions and composed of areas that integrate incoming information from different sensory organs.
a system of functionally related neural structures in the brain that are involved in emotional behavior
short term memory
activated memory that holds a few items briefly, such as the seven digits of a phone number while dialing, before the information is stored or forgotten
long term memory
the relatively permanent and limitless storehouse of the memory system. Includes knowledge, skills, and experiences
Long term depression, a reduction in the efficiency of a neuronal synapse that can last an hour or more. occurs in cerebellum and is input specific. decreased response in glutamate poss due to internalization of its recpetors
Long Term Potentiation, An increase in a synapse's firing potential after brief, rapid stimulation. Believed to be a neural basis for learning and memory.