CENTRAL NERVOUS SYSTEM The complex of nerve tissues that controls the activities of the body. It’s made up of the brain and spinal cord. Spinal cord controls monosynaptic reflex Brain controls polysynaptic reflex

PERIPHERAL NERVOUS SYSTEM The peripheral nervous system (PNS) is the part of the nervous system that consists of the nerves and ganglia on the outside of the brain and spinal cord. Extremities of the body

AUTONOMIC NERVOUS SYSTEM The part of the nervous system responsible for control of the bodily functions not consciously directed, such as breathing, the heartbeat, and digestive processes.

SOMATIC NERVOUS SYSTEM The somatic nervous system is the part of the peripheral nervous system associated with skeletal muscle voluntary control of body movements.

PARASYMPATHETIC NERVOUS SYSTEM The parasympathetic nervous system is one of the divisions of the autonomic nervous system. Sometimes called the rest and digest system, the parasympathetic system conserves energy as it slows the heart rate, increases intestinal and gland activity, and relaxes sphincter muscles in the gastrointestinal tract.

SYMPATHETIC NERVOUS SYSTEM The part of the autonomic nervous system that contains chiefly adrenergic fibers and tends to depress secretion, decrease the tone and contractility of smooth muscle, and increase heart rate. When in a stressful situation, this system takes over your body. Often called the “fight or flight” system

NEURONS Cells of the nervous system specialized to transmit messages throughout the body.

DENDRITES A short branched extension of a nerve cell, along which impulses received from other cells at synapses are transmitted to the cell body.

CELL BODY The dendrites connect to the cell body of the neuron. This contains the nucleus of the neuron which contains all of it’s information.

AXON The long threadlike part of a nerve cell along which impulses are conducted from the cell body to other cells. The axon has links within its threadlike structure that are called nodes of ranvier that enhance mobility.

MYELIN AND UNMYELINATED Myelin is a mixture of proteins and phospholipids forming a whitish insulating sheath around the axon, increasing the speed at which impulses are conducted. An example of myelination is the formation of myelin around the axons of the body. Other axons are unmyelinated, meaning that the myelin sheath is not present, the signals are unable to reach the action potential.

AXON TERMINAL The axon terminal is the somewhat enlarged, often club-shaped endings by which axons make synaptic contacts with other nerve cells or with effector cells. Axon terminals contain neurotransmitters of various kinds, sometimes more than one.

SYNAPSE A synapse is the tiny gap across which a nerve cell, or neuron, that can send an impulse to another neuron. When all your synapses are firing, you're focused and your mind feels electric. Happens when a neuron reaches action potential.

NERVE IMPULSE A nerve impulse is a signal transmitted along a nerve fiber. It consists of a wave of electrical depolarization that reverses the potential difference across the nerve cell membranes.

DEPOLARIZATION Depolarization is the loss of the difference in charge between the inside and outside of the plasma membrane of a muscle or nerve cell due to a change in permeability and migration of sodium ions to the interior.

REPOLARIZATION Repolarization refers to the change in membrane potential that returns it to a negative value just after the depolarization phase of an action potential has changed the membrane potential to a positive value.

ACTION POTENTIAL An action potential is the change in electrical potential associated with the passage of an impulse along the membrane of a muscle cell or nerve cell.

REFRACTORY PERIOD The refractory period is a period immediately following stimulation during which a nerve or muscle is unresponsive to further stimulation.

K/NA+ PUMP Causes the action potential in neurons due to the exchange in sodium and potassium.

CONDUCTIVITY This means neurons are also able to transfer an impulse along the full length of their axons and then on to other neurons, muscles or glands.

IMPULSIVITY Transmit impulses to other nerve cells and neurons. The only thing able to relay messages through impulsivity.

POLARIZATION When sodium is on the outside, and potassium is on the inside which causes the membrane to be polarized.

IRRITABILITY Ability to convert a stimulus to a nerve impulse.

AFFERENT NEURON The peripheral nervous system, an afferent nerve fiber is the nerve fiber (axon) of an afferent neuron (sensory neuron).

INTEGRATION CENTER Happens within the brain or spine and it changes afferent impulses into efferent neurons.

EFFERENT NEURON A neuron conducting impulses outwards from the brain or spinal cord. Motor neuron, motor nerve fiber, motor neuron.

HOMEOSTATIC IMBALANCES Alzheimer’s Disease- Progressive degeneration of the brain with abnormal protein deposits. Meningitis- swelling and irritation (inflammation) of the membranes covering the brain and spinal cord Parkinson’s Disease- a degenerative disorder of the central nervous system that often impairs the sufferer's motor skills, speech, and other functions. Huntington’s Disease- A human genetic disease caused by a dominant allele; characterized by uncontrollable body movements and degeneration of the nervous system; usually fatal 10 to 20 years after the onset of symptoms.

1. WHAT IS KNOWN AS THE “FIGHT OR FLIGHT” RESPONSE? A.Parasympathetic Nervous System B.Sympathetic Nervous System C.Somatic Nervous System

B. Sympathetic nervous system

2. WHAT SURROUNDS THE AXON? A.Dendrites B.Nodes of Ranvier C.Myelin

3. WHAT ARE THE NOTCHES IN THE AXON? A.Nodes of Ranvier B.Synapse C.Dendrites

A. Nodes of Ranvier

4. WHAT RECEIVES THE NEURON IMPULSES? A.Axon Terminal B.Synapse C.Dendrites

5. WHAT TWO ELEMENTS CAUSE AN ACTION POTENTIAL? A.Sodium and Potassium B.Sodium and Hydrogen C.Hydrogen and Potassium

A. Sodium and Potassium

6. Dendrites 7. Cell Body 8. Axon 9. Nodes of Ranvier 10.Axon Terminal 11. Nucleus 12. Myelin