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Jazmine Mendez P.7 Nervous System - Coggle Diagram
Jazmine Mendez
P.7 Nervous System
Tissues
Neurons
myelinated fibers - large axons are enclosed by myelin sheaths
dendrites- conduct impules toward cell body
Nodes of Ranvier- narrow gaps in the myelin sheaths
cell body(soma)- contains major organelles
Neuroglia
Astrocytes
lie between blood vessels and neurons
Peripheral Nervous System
Satellite cells- produce protective coating around cel bodies of neurons PNS
Schwann cells - myelin producing neuroglia of PNS
Ependymal cells
produce cerebrospinal fluid in CNS
Oligodendrocytes
form the myelin sheath around axons in the brain
Microglia
small cells that function as phagocytes for bacterial cells and cellular debris
Major parts and functions of the brain
Cerebellum
coordinates skeletal muscle
ensures movement occurs in desired manner
integrates sensory info about position of body part
Cerebral Cortex
Pariteal lobe
Cutaneous Senses
anterior parietal lobe
function in understanding speech and choosing words
Frontal lobe
control a number of higher intellectual process
Occipital lobe
Visual area
posterior occipital lobe
help analyze visual patterns and combine visual images
Temporal lobe
Auditory area
posterior temporal lobe
Smell area
deep temporal lobe
helps understand written and spoken language
Primary motor cortex
frontal lobes and central sulcus; crossover in brainstem in motor system
Broca's motor speech area
controls muscle movement for speech found in frontal lobe
Basal Nuclei
masses of gray matter(nuclei)- located deep within cerebral hemisphere; and help facilitate voluntary movement
Ventricles and CSF
cerebra spainal fluid a central connects of spine cord
ventricles a series of connected cavities within cerebral hemisphere and brainstem
third ventricle
cerebral aqueduct
fourth ventricle
Choroid Plexuses
found in ventricles; CSF into ventricles arise in lateral ventricels
CSF surrounds brain and spinal cord
Diencephalon
main parts are the thalamus and hypothalamus
lies between cerebral hemisphere and above midbrain
Thalamus
sorting and directing sensory info arriving from other parts
channels all sensory impulses
Hypothalamus
regulates body temp and blood pressure
maintains homeostasis by regulating wide variety of viseral activities and linking endocrine system
The Limbic System
area of diencephalon, controls emotionl expirence and expressive
modifies behavior by producing feeling of fear
Brain stem
Pons
lies between midbrain and medulla oblongata
containg centers that help regulate the rate and depth of breathing
Midbrain
located betwen diencephalon and pons
contains main motor pathways between cerebrum and lower portions
Medulla oblongata
Cardiac center
transmits all ascending and descending impulses
Vasomotor center
respiratory center
lies base of cerebrum
Reticular Formation
network of nerve fibers connecting small masses of gray matter
decreased activity in reticular formation
Cerebrum- largets portion of mature brain
Sulci-grooves
Gyri-ridges
Fissures- deep groves
Corpus Callosum - flat bundle of nerve fibers
Major divisions and subdivisions of the nervous system
Peripheral Nervous System
contains sensory(afferent) and motor (efferent)
made of cranial nerves and spinal nerves that connect CNS
Central Nervous System
made of brain and spinal cord
responsible for integration of info and decsion-making
Somatic Nervous system
controls voluntary skeletal muscles
Autonomic Nervous system
controls involuntary effectors
Classification of neurons
Bipolar neurons- 2 processes extending from cell body
Unipolar neurons- only 1 process extending from cell body
Multipolar neurons - many dendrities and are axon arising from their cell bodies
Interneurons(association or internuncial neurons)- multipolar neurons lying within CNS that form links between other neurons
Motor(efferent neurons) - multipolar neurons that conduct impulses from CNS to peripheral effectors
Sensory (afferent) neurons- conduct impulses from peripheral recepters to CNS
Cranial nerves
12 pairs of cranial nerves
most are mixed nerves
Connective Tissue Covering
Perineurium - covering fascicles(bundles) nerve fibers
Endoneurium- covering around individual nerve fibers
Epineurium- outer covering of nerve
Major parts and functions of the spinal cord
Cauda equina - structure formed where spinal cord tapers to point inferiorly
white matter- bundles of myelinated nerve fibers
Lumbar enlargment- thickend region near bottom of spinal cord
gray matter- housing interneuorns and neuron cell bodies
Cervical enlargement-thickend area near top of Spinal cord
Action potiental and Nerve Impulse
Action potiential occurs when charge reaches -55mV
Refractory period - action potential , a threshold stimulus will not cause another action potentials
Continuous conduction- occurs in unmyelinated axons
Saltatory conduction- occurs in myelinated axons
Major Functions of Nervous system
Integrative Function
coordination of sensory info to CNS
processing of info in basis for decsion-making
Motor Function
effectors-muscles or glands that respond to decsion made
nerve impulses (CNS) conducted along motor neurons to effectors
Sensory Function
info travels from receptors to sensory neurons, which transport info to CNS
sensory receptors, which detect internal or extermal charges
Spinal Nerves
8 pairs of cervical nerves
31 pairs arise from spinal cord
12 pairs thoracic nerves
5 pairs lumbar nerves
1 pair of coccygeal nerves
motor ventral root
sensory dorsal root
dorsal root ganglion
Neurotransmitters
chemical messangers in a synapse, that convey an electrical impulses from a neuron to another cell
Peripheral Nervous System
Automomic Nervous system - connects CNS to viscera, and controls subconscious activites
Somatic Nervous System - connects CNS to skeletal muscles and skin
craninal nerves arsing from brain and spinal nerves and spinal cord
Reflex arc
Withdrawl reflex - occurs in response to touching something painful
Patellar( kneew jerk) reflex - simple reflex has 2 neurons, senosory and motor