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Nervous System Stephanie Zaragoza P2 - Coggle Diagram
Nervous System Stephanie Zaragoza P2
Major functions of the nervous system
sensory input,information processing,motor output
sensory receptor neurons respond to stimuli and send signals of information to CNS
with the endocrine system, the nervous system is responsible for regulating and maintaining homeostasis
memory and learning
Major divisions and subdivisions of the nervous system (include all subdivisions of CNS
and PNS)
the nervous system is divided into 2; the central nervous system(CNS) and peripheral nervous system(PNS)
Central Nervous System
:
F: integration of info and decision making
contains brain and spinal cord
central nervous system neuroglia
Microglia: small cells that function as phagocytes for bacterial cells and cellular debris, produce scar tissue in injury sites
oligonucleotides: form the myelin sheath around axons in the brain and spinal cord
Ependymal Cells: produce csf in the cns
Peripheral Nervous System
contains: cranial and spinal nerves that connect the cns to the rest of the body
F: has sensory and motor divisions
Somatic Nervous system
connects cns ti the skeletal muscles and the skin, oversees conscious activities
Autonomic Nervous System
connects cns to viscera and controls subconscious activities
Tissues (structure & function of neurons and neuroglia)
Structures
uni polar
-fused axon & dendrite; found in skin,joints,muscles, and internal organs
bipolar
:one dendrite & one axon
multipolar
: has many dendrites & one axon
Neurogolia Function:
maintaining homeostatic control and immune surveillance in the nervous system.
support,nourish,protect,and insulate neurons
Neuron Functions:
neurons are are specialized nerve cells that generate and transfer electrical impulses throughout the body
Classification of neurons
motor neurons
: multipolar neurons that conduct impulses from the cns to the peripheral effecors(muscles/glands)
Sensory neurons
: conduct impulses from perioheral recpetors to the cns; unipolar-some bipolar
interneurons
: multipolar neurons lying within the cns that form links between other neurons
Connective Tissue Coverings
endomysium
separates single muscle fibers from one another
adapts itself to the changes of volume that occur during the muscle fiber contraction.
perimysium
groups muscle fibers into bundles (anywhere between 10 and 100 or more) or fascicles
Connective tissues bind structures together, form a framework and support for organs and the body
epimysium
allows a muscle to contract and move powerfully while maintaining its structure
separates muscle from other tissues and organs in the area, allowing the muscle to move independently
Major parts and functions of the brain
major parts
cerebrum
performs higher functions like interpreting touch, vision and hearing, as well as speech, reasoning, emotions, learning, etc.
cerebellum
coordinates muscle movements, maintain posture, and balance.
located underneath the cerebrum
brainstem
performs automatic functions such as breathing, heart rate, body temperature, wake and sleep cycles, digestion, sneezing, coughing, vomiting, and swallowing
Major parts and functions of the spinal cord
Motor Functions - directs your body's voluntary muscle movements.
Sensory Functions – monitors sensation of touch, pressure, temperature and pain.
Autonomic Functions – regulates digestion, urination, body temperature, heart rate, and dilation/contraction of blood vessels (blood pressure).
F: transmit impulses to and from the brain and to house spinal reflexes
spinal reflexes: controlled by reflex arcs that pass through the spinal cord
ascending tracts: carry sensory info to the brain
descending tracts: carry motor info from brain to muscles and glands
Spinal Nerve Plexuses:
Cervical : lies on either side of the neck, supply muscles and skin of the neck
included the phenic nerves that control the diaphragm
Brachial: from lower cervical and upper thoracic nerves; supply muscles and skin of arms,forarms, and hands; lead into upper limbs
Lumboscarrcal: supply muscles and skin of the lower abdomen and etc
intercostal: anterior branches of the thoracic spinal nerves do not form plexus and become intercostal
Action potential & the Nerve Impulse
an electrical charge that travels along the membrane of a neuron.
membrane potential: the charge inside a cell
resting membrane potential : the charge in a cell when it is at rest; about -70 mv in neurons
Charges inside a cell: when a cell is polarized the charge inside the membrane is different from outside the membrane
Action potentials are created by the special types of voltage ion channels that are in a cell's plasma membrane
threshold stimulus: strong enough to get na+ ions to enter neuron
depolarization: change from neg. to positive inside neuron
Cranial nerves
Olfactory: Smell
Optic: Sight
Oculomotor:
Eye movement
Pupillary constriction
Accommodation
Eyelid opening
Trochlear: eye movement
Trigeminal
Facial sensation
Mastication
Abducens: Eye movement (lateral rectus muscle)
Facial
Facial movements
Taste from anterior ⅔ of tongue (chorda tympani)
Lacrimation
Salivation
Eyelid closing
Auditory reflex
Vestibulocochlear
Hearing
Balance
Glossopharyngeal
Taste and sensation of posterior of tongue
Monitoring of carotid body and sinus chemoreceptors and baroreceptors
Elevation of pharynx/larynx
Vagus
Swallowing
Speech
Cough reflex
Accessory
Head turning
Shoulder shrugging
Hypoglossal
Tongue movements
Spinal nerves
total of 31 pairs of spinal nerves control motor, sensory, and other functions
-These nerves are located at the cervical, thoracic, lumbar, sacral, and coccygeal
8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal.
:
Cervical Plexus:
these divide into smaller nerves that carry sensory messages and provide motor control to the muscles of the neck and shoulders.
Brachial Plexus:
this plexus branches into nerves that carry sensory messages and provide motor control to the muscles of the arm and upper back.
Lumbar Plexus
: this plexus splits into nerves that carry sensory messages and provide motor control to the muscles of the abdomen and leg.
Sacral Plexus:
carry sensory messages and provide motor control to the muscles of the legs.
Coccygeal Plexus
:this plexus supplies motor and sensory control of the genitalia and the muscles that control defecation.
Neurotransmitters
: chemical messengers in a synapse that send electrical impulse from a neuron to another cell
many necessary functions, including heart rate
transmit signals from nerve cells to target cells that may be in muscles, glands, or other nerves
Compare & contrast the autonomic nervous system
Somatic Nervous System
:
connects the CNS to Skeletal muscles and the skin & oversees conscious activities
controls muscles and movement
Autonomic Nervous System
connects the CNS to viscera and controls subconscious activities
controls internal organs and glands
helps maintain homeostasis,responds to emotional stress, & prepares body for activity
autonomic activities are regulated by reflexes that have sensory receptors in the viscera and skin
Reflex arc (major parts & functions)
a series of events of a reflex response
first,sensory receptor detects stimuli
then,afferent neurons send signals to CNS
lastly, the motor neuron delivers a response reaction to target the organ from where the stimulation came from,then the organ respond
3rdly, synapse makes a connection between sensory & motor neuron
Includes:
sensory receptor.
sensory neuron.
integration center.
motor neuron.
effector target.
Sensory cells carry input from the receptor (afferent impulses) to a central interneuron, which makes contact with a motor neuron
