Nervous System Flashcards
What are the nervous systems three broad functions?
Sensory
Integrative
Motor
One of the body’s principal control and integrating centers, and the other is the endocrine system.
THE NERVOUS SYSTEM
What are the two main parts of the nervous system?
The central nervous system cns
The peripheral nervous system pns
What is the central nervous system made up of?
Brain and spinal cord
All nerve tissue outside of the spinal cord and brain are part of what system?
- NERVES THAT CONNECT THE BRAIN AND SPINAL CORD (Cns) WITH RECEPTORS, MUSCLES AND GLANDS
Peripheral nervous system pns
What are the two types of cells found in the nervous system?
Neurons
Neuroglia
Highly specialized cells for nerve impulse conduction and for all special functions attributed to the nervous system: thinking, controlling, activity, and regulating glands.
Not capable of mitosis
Neurons
What are the three basic parts of each neuron?
The cell body (soma)
One or more dendrites
Single axon
What are neurons classified as?
Afferent, efferent, or interneurons
- or sensory, neurons carry impulses from peripheral sense receptors to the CNS
- are the first cells to pick up incoming information
Afferent neurons
- or motor, neurons transmit impulses from the cns to the effector organs such as muscles and glands
- nerve cells within the efferent systems
Efferent neurons
Are located entirely within the cns in which they form the connecting link between the afferent and efferent neurons
Interneurons
-are afferent processes that transmits impulses to the neuron cell body.
Dendrites
What projects from the cell body and is an efferent process that carries impulses away from the cell body
Axon
Are the distal ends of the telodendria that are slightly enlarged to form what ?
Synaptic bulbs
Some axons are wrapped in a myelin sheath formed from the plasma membranes of specialized glial cells known as
Schwann cells
Are connective tissues cells that do not conduct nerve impulses, but instead, they support and nourish and protect the neurons.
Neuroglias
A cordlike structure consisting of a collections of nerve fibers (neurons) that convey impulses
Nerve
Is the control center for the entire nervous system and consists of the brain and spinal cord
Central Nervous System
Cns
What three parts is the brain divided into
Cerebrum
Cerebellum
And brain stem
What is the structure that divides the cerebrum into two hemispheres
Corpus Callosum
Is a region of the brain that plays an important role in the integration of sensory perception and motor output.
Cerebellum
Each hemisphere is divided into four lobes? What are they
Frontal, temporal, parietal, occipital
Is continuous with the spinal cord, it is composed of the medulla oblongata, the pons, and the midbrain
- it relays information from the body to the brain and vice versa
- regulates the cardiovascular system, pain respiration, pain sensitivity, alertness and consciousness
Brain stem
Is a cylindrical bundle of nerves that is slightly flattened anteriorly and posteriorly
Spinal cord
The spinal cord is composed of what matter?
Gray and white matter
Is where the cell bodies located, is found in the central portion of the spinal cord.
Gray matter
Where the axons of the spinal cord are located
White matter
The brain and spinal cord are covered by three layers of tissue known collectively as the
The meninges
What are the three layers of the meninges
Pia mater
Arachnoid mater
Dura mater
Inner most layer of the meninges
-it closely adheres to the brain and spinal cord
Pia mater
A layer that has a spider web appearance
-it serves to cushion the cns
Arachnoid layer
The thicker most outer layer of the meninges.
Dura mater
Associated with motor skills (including speech) and cognitive functions (reasoning, planning emotion)
Frontal lobe
Associated with sensory processing and understanding language,.
Parietal lobe
Associated with visual processing
Occipital lobe
Is with in the cerebrum and continuos with the mid brain (brain stem)
Includes the thalamus and hypothalamus
The diencephalon
Is involved in relaying motor and sensory information to the cerebral cortex as well as regulating consciousness sleep and alertness
The thalamus
Regulates thirst, hunger, body temperature, and the circadian rhythm. ( the body’s 24 hour biological cycle)
- it also connects with and controls the pituitary gland
Hypothalamus
Consists of nerve cells that convey information from receptors in the periphery of the body to the cns
Afferent system
Consist of nerve cells that convey information from the cns to the muscles and glands. It is divided into the somatic and the autonomic nervous systems
Efferent systems
Consists of efferent neurons that conduct impulses from the cns to the skeletal muscle tissue. It is under conscious control and therefore is considered voluntary
Somatic nervous system
Contains efferent neurons that convey impulses from the central nervous system to smooth muscle tissue, cardiac muscle tissue, and glands
Autonomic nervous system
-stimulates some visceral action and inhibits others.
Stimulates heartbeat, raises BP, dilates pupils, dilates the trachea and bronchi, stimulates the conversion of liver glycogen into glucose, shunts blood away from the skin and to the viscera to the skeletal muscles, brain, and heart
Sympathetic nervous system
Slowing down of the heart beat, lowering of BP, constriction of pupils , increased blood flow to the skin and viscera, peristalsis of the GI Tract
Parasympathetic nervous system
The junction between a nerve cell and another cell
Synapse
The space between two cells is known as
Synaptic cleft
Name three types of neurotransmitters
Acetylcholine, norepinephrine, dopamine
-there are 12 pairs, and designated with roman numerals and names. Pns
Olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, hypoglossal
Cranial nerves
True or false
There are 31pairs of spinal nerves that branch off the spinal cord: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1coccygeal.
True!!!!
Networks on either side of the body created by the grouping of adjacent nerves
Plexus
First four cervical nerves (c1-c4) with contributions from c5
Cervical plexus
Formed by the spinal nerves c5-c8 and t1
- it constitutes the entire nerve supply for the upper extremity and part of the shoulder region
Brachial plexus
Supplies the deltoid and TERES minor muscles
Axillary nerve
Supplies the flexors of the arm and forearm
Musculocutaneous nerve
Supplies the muscles on the posterior aspect of the arm and forearm
Radial nerve
Supplies most of the muscles of the anterior forearm and some of the muscles in the palm of the hand
Median nerve
Supplies the anteromedial muscles of the forearm and most of the muscles of the palm of the hand
Ulnar nerve
Spinal nerves L1-L4
Lumbar plexus
Spinal nerves L4,L5, and s1-s4. It supplies the buttocks, perineum and much of the lower extremities.
Sacral plexus
The largest nerve arising from the sacral plexus and the largest nerve in the body. It supplies the entire musculature of the leg and foot
Sciatic nerve
Spinal nerve T2-T11, do not enter into the formation of the plexuses. These nerves are distributed directly to the structures they supply in the intercostal spaces
Thoracic nerves