Name:_____________________________________________

The Nervous System OutlineFunctions of the Nervous System __________________ —gathering information To monitor _________________ occurring inside and outside the body _________________= stimuli _________________ To process and interpret _________________input and decide if _________________is needed _________________ A _________________to integrated stimuli The response activates _____________or____________

Structural Classification of the Nervous System _________________nervous system (CNS) _________________ _________________ _________________nervous system (PNS) _________________outside the brain and spinal cord _________________nerves _________________nerves

Functional Classification of the Peripheral Nervous System _________________ (_________________) division Nerve fibers that carry information ________ the central nervous system Motor (_________________) division Nerve fibers that carry impulses ___________ from the central nervous system Two subdivisions _________________nervous system = voluntary _________________nervous system = involuntary

Nervous Tissue: Support Cells Support cells in the CNS -“_______________________” Function: to ___________, insulate, and __________

neurons _________________ Abundant, __________-shaped cells Brace neurons Form barrier between _________________and neurons Control the _________________environment of the brain _________________ Spiderlike phagocytes _________________of debris _________________cells Line _________________of the brain and spinal cord Circulate _________________fluid _________________ Wrap around nerve fibers in the central nervous system Produce myelin _________________ _________________ cells _________________neuron cell bodies _________________cells Form myelin _________________in the peripheral nervous system

Nervous Tissue: Neurons _________________= nerve cells Cells specialized to _________________messages Major regions of neurons _________________—nucleus and metabolic center _________________—fibers that extend from cell body Cell body _________________substance Specialized _________________________ reticulum _________________ Intermediate cytoskeleton Maintains cell _________________ Cell body _________________ Large _________________ Processes outside the cell body _____________—conduct impulses toward the cell body _____________—conduct impulses away from the cell body Axons end in axonal _________________

Axonal terminals contain vesicles with _________________ Axonal terminals are separated from the next neuron by a _____ _________________—gap between ____________neurons _________________—junction between nerves Myelin _____________—whitish, fatty material covering axons ________________cells—produce myelin ___________ in jelly roll–like fashion Nodes of __________—______ in myelin sheath along the axon

Neuron Cell Body Location Most neuron cell bodies are found in the ______ nervous system __________matter—cell bodies and ______________fibers __________—clusters of cell ___________ within the white matter of the _______ nervous system ______________—collections of cell bodies outside the central nervous system

Functional Classification of Neurons _________________ (afferent) neurons Carry impulses from the sensory receptors ____ the CNS Cutaneous sense organs _________________—detect stretch or tension _________________ (efferent) neurons Carry impulses ________ the central nervous system to viscera, ___________, or ___________ _________________ (association neurons) Found in neural pathways in the central nervous system Connect _______________and ______________neurons

Structural Classification of Neurons _______________neurons—many extensions from the cell body

_______________neurons—one axon and one dendrite

_______________neurons—have a short single process leaving the cell body

Functional Properties of Neurons _________________ Ability to respond to _________________ _________________ Ability to transmit an _________________

Nerve Impulses Resting neuron The plasma membrane at rest is _________________ _____________positive ions are inside the cell than outside _________________ A stimulus depolarizes the neuron’s _________________

A depolarized membrane allows ___________ (Na+) to flow _________________ the membrane The exchange of ions initiates an ________ ________________ _________________potential If the action potential (nerve _________________) starts, it is propagated over the _________________axon Impulses travel ________ when fibers have a myelin sheath _________________ Potassium ions rush ______ of the neuron after sodium ions rush in, which _________________the membrane The _________________ pump, using _______, restores the original configuration

Transmission of a Signal at Synapses Impulses are able to ___________ the synapse to another nerve ________________is released from a nerve’s axon terminal The ___________________ of the next neuron has receptors that are stimulated by the neurotransmitter An action potential is started in the _________________

The Reflex Arc ______________—rapid, _______________, and involuntary response to a stimulus Occurs over pathways called reflex ________ Reflex arc—_____________ route from a __________ neuron, to an ____________, to an ______________

Types of Reflexes and Regulation

_________________reflexes Activation of skeletal muscles Example: _________________reflexes _________________muscle regulation Heart and blood pressure regulation Regulation of glands Digestive system regulation _________________, or knee-jerk, reflex is an example of a __________-neuron reflex arc

Central Nervous System (CNS) CNS develops from the embryonic neural tube The neural tube becomes the __________ and __________ The opening of the neural tube becomes the ventricles _______ chambers within the brain Filled with _________________fluid

Regions of the Brain _________________ hemispheres (_________________) _________________ _________________ stem _________________

Regions of the Brain: Cerebrum Cerebral Hemispheres (Cerebrum) _______________ (left and right) superior parts of the brain Includes more than ___________ of the brain mass The surface is made of ridges (_____) and grooves

(______) Lobes of the cerebrum ___________ (deep grooves) divide the cerebrum into lobes Surface lobes of the cerebrum _________________lobe _________________lobe _________________lobe _________________lobe

Specialized areas of the cerebrum Primary _________________ sensory area Receives impulses from the body’s ________ receptors Located in _________________lobe Primary _________________area Sends impulses to _________________muscles Located in _________________lobe _________________area Involved in our ability to _________________ Cerebral areas involved in special senses _________________area (taste) _________________area _________________area _________________area Interpretation areas of the cerebrum Speech/_________________region Language _________________region General _________________area

Layers of the cerebrum ___________ matter—_______ layer in the cerebral cortex composed mostly of neuron cell bodies ___________ matter—fiber tracts ______ to the gray matter Corpus _________________ connects hemispheres ________ nuclei—islands of _________ matter buried within the white matter

Regions of the Brain: Diencephalon Sits on top of the ___________ stem _________________ by the cerebral hemispheres Made of three parts _________________ _________________ _________________ Thalamus Surrounds the ____________ ventricle The __________ station for sensory impulses Transfers impulses to the correct part of the cortex for localization and interpretation Hypothalamus _____________ the thalamus Important _________________ nervous system center Helps regulate body __________________ Controls __________ balance Regulates _________________ An important part of the __________ system (__________)

The ____________ gland is attached to the hypothalamus

Epithalamus Forms the ______________ of the third ventricle Houses the ____________ body (an endocrine gland) Includes the _________ plexus—forms ____________ fluid

Regions of the Brain: Brain Stem Attaches to the ______________ cord Parts of the brain stem _________________ _________________ _________________ _________________ Midbrain Mostly composed of ____________ of nerve fibers Has ______ bulging fiber tracts— cerebral peduncles Has ______ rounded protrusions— corpora quadrigemina Reflex centers for _________ and ___________ Pons The bulging __________ part of the brain stem Mostly composed of fiber tracts Includes nuclei involved in the control of ______________ Medulla Oblongata The _________________part of the brain stem _________________into the spinal cord Includes important fiber tracts Contains important control centers _________ rate control Blood __________ regulation ___________ ___________ ___________ _________________Formation Diffuse mass of gray matter along the brain stem Involved in ________ control of visceral ____________ Reticular activating system (RAS) plays a role in _________________cycles and consciousness

Regions of the Brain: Cerebellum

___________ hemispheres with convoluted surfaces Provides involuntary ________________ of body movements

Protection of the Central Nervous System Scalp and __________ __________ and vertebral column Meninges _________________ fluid (CSF) _________________ barrier

Meninges ___________ mater Double-layered _______________ covering _____________—attached to inner surface of the skull _____________ layer—outer covering of the brain Folds inward in several areas ___________________ layer Middle layer; Web-like __________ mater Internal layer Clings to the _______________ of the brain

Cerebrospinal Fluid (CSF) Similar to blood _________________composition Formed by the choroid plexus Forms a watery _________________to protect the brain Circulated in ________________ space, ______________, and ______________ canal of the spinal cord

Hydrocephalus in a Newborn Hydrocephalus CSF _________________and exerts ________________on the brain if not allowed to drain

Blood-Brain Barrier Includes the least _________________ capillaries of the body Excludes many potentially ________________ substances Useless as a barrier against some substances ___________ and fat soluble molecules

__________________ gases _______________ _______________ _______________

Traumatic Brain Injuries _________________ Slight brain injury ________ permanent brain damage _________________ Nervous tissue destruction occurs Nervous tissue _______________ regenerate Cerebral ______________ _________________ from the inflammatory response May compress and _____________ brain tissue

Cerebrovascular Accident (CVA) Commonly called a ______________ The result of a _________________ blood vessel supplying a region of the brain Brain tissue supplied with oxygen from that blood source _____ Loss of some functions or _____________ may result

Alzheimer’s Disease Progressive _____________________ brain disease Mostly seen in the ___________, but may begin in middle age ________________ changes in the brain include abnormal protein deposits and twisted fibers within neurons Victims experience memory _________, irritability, ___________, and ultimately, ___________________ and death

Spinal Cord Extends from the foramen ______________ of the skull to the first or second _______________ vertebra ________ pairs of spinal nerves arise from the spinal cord _________________-collection of spinal nerves at inferior end

Spinal Cord Anatomy

Internal _________ matter is mostly cell bodies Dorsal (____________) horns Anterior (_____________) horns Gray matter surrounds the ___________ canal Central canal is filled with __________________ fluid Exterior __________ mater—conduction tracts Dorsal, lateral, ventral columns _________________ cover the spinal cord Spinal nerves leave at the level of each _________________ ______________root Associated with the dorsal root ganglia—collections of cell ___________ outside the central nervous system _____________ root Contains axons

Peripheral Nervous System (PNS) _____________ and ganglia outside the central nervous system _____________ = _____________ of neuron fibers Neuron fibers are bundled by _________________ tissue

PNS: Structure of a Nerve ___________________ surrounds each fiber Groups of fibers are bound into __________ by _____________ Fascicles are bound together by ____________________

PNS: Classification of Nerves ____________ nerves Both _________ and _________ fibers Sensory (________________) nerves Carry impulses ______________ the CNS Motor (_______________) nerves Carry impulses _____________ from the CNS

PNS: Cranial Nerves ______ pairs of nerves that mostly serve the ______ and _____ Only the pair of __________ nerves extend to thoracic and

abdominal cavities Most are __________ nerves, but three are _________ only I _____________ nerve—sensory for smell II ____________ nerve—sensory for vision III ____________ nerve—motor fibers to eye muscles IV ____________ —motor fiber to eye muscles V ____________ nerve—sensory face; motor-chewing muscles VI ____________ nerve—motor fibers to eye muscles VII ____________ nerve—sensory for taste; motor to the face VIII ________________________nerve—sensory for balance and hearing IX ________________________ nerve—sensory for taste;

motor fibers to the pharynx X __________ nerves—sensory and motor fibers for pharynx,

larynx, and viscera XI _________ nerve—motor fibers to neck and upper back XII _________________ nerve—motor fibers to tongue

PNS: Spinal Nerves There is a pair of spinal nerves at the level of each vertebrae for a total of ____ pairs Formed by the combination of the ventral and dorsal roots of the spinal cord Named for the region from which they ____________

PNS: Anatomy of Spinal Nerves Spinal nerves divide soon after leaving the spinal cord _________ _________—serve the skin and muscles of the posterior trunk _________ _________—form a complex of networks (_____________) for the anterior

PNS: Autonomic Nervous System _______________ subdivision of the PNS Consists only of motor nerves Also known as the ________________ nervous system Regulates activities of cardiac and smooth ___________

and __________________ _________ subdivisions ___________________ and ___________________

PNS: Differences Between Somatic and Autonomic Nervous Systems Nerves Somatic: ____________ motor neuron Autonomic: _____________ and _____________ nerves Effector organs Somatic: _____________ muscle Autonomic: ___________ muscle,_____________ muscle, and ______________ Neurotransmitters Somatic: always use _____________________ Autonomic: use _________________, _________________, or __________________

PNS: Autonomic Functioning

___________________—“fight or flight” Response to unusual ______________ Takes over to _____________ activities Remember as the “E” division ______________, ______________, ______________,

and ______________ ___________________—“housekeeping” activites ______________energy ______________daily necessary body functions Remember as the “___” division ____________, ____________, and ____________

Development Aspects of the Nervous System Formed during the ___ month of embryonic development Any maternal ____________can have extremely harmful effects The ______________ is one of the last areas of brain to develop No more ____________ are formed after birth, but growth and maturation continues for _____________ years The brain reaches maximum ____________ as a young adult