Please enable JavaScript.
Coggle requires JavaScript to display documents.
The Nervous System Julianna Soto Period 2 (tissues (Dendrites (responding…
The Nervous System
Julianna Soto Period 2
Major functions
Integration
decides what should be done at each moment
Motor output
cause response as it activates effector organs
Sensory input
monitor changes occurring both inside and outside the body
divisions
Central nervous system
consists of the brain and spinal cord that occupy the dorsal cavity
sensory input; dictates motor output based on reflexes ,conditions and past experiences
Peripheral nervous system
consists of nerves(bundles of axons) that extend throughout the body
Spinal nerves carry impulses to and from the spinal cord ; cranial nerves carry impulses to and from the brain.
Subdivisions
CNS
motor/efferent division
somatic nervous system
conduct impulses from the CNS to skeletal muscles, allows to control skeletal muscles
autonomic nervous system
Regulate activity of the smooth,cardiac muscles and glands
PNS
sensory/afferent divisions
Somatic sensory fibers
convey impulses from the skin,skeletal muscles and joints
Visceral sensory fibers
transmit impulses from the visceral organs
Major parts of the brain and functions
The Cerebral Cortex
outermost portion that can be divided into the four lobes of the brain
The Brain Stem
medulla
located above the spinal cord in the lower part of the brain stem and controls many vital autonomic functions
pons
connects the medulla to the cerebellum
stimulating breathing and controlling sleep cycles.
midbrain
controls the visual and auditory systems as well as eye movement
The Cerebellum
receives information from the balance system of the inner ear, sensory nerves, and the auditory and visual systems
Thalamus
thalamus processes and transmits movement and sensory information
lobes and their functions
The parietal lobe
processing tactile sensory information pressure, touch, and pain
The temporal lobe
interpreting sounds and the language we hear
Damage to the temporal lobe can lead to problems with memory, speech perception, and language skills.
The frontal lobe
associated with reasoning, motor skills, higher level cognition, and expressive language
Damage to the frontal lobe can lead to changes in sexual habits, socialization, and attention
occipital lobe
interpreting visual stimuli and information
Damage to this lobe can cause visual problems , recognizing objects, an inability to identify colors, and trouble recognizing words.
layers of meninges
arachnoid mater
loosely covers the brain and spinal cord and gets its name from its web-like appearance.
pia mater
closely covers the cerebral cortex and spinal cord
produce cerebrospinal fluid
dura mater
meningeal
forms dural folds that divide the cranial cavity into different compartments, which support and house various subdivisions of the brain
periosteal
connects the dura mater to the skull and covers the meningeal layer
spaces and ventricles
subdural space
between the dura mater and the middle layer of the meninges, the arachnoid mater
subarachnoid space.
between the arachnoid membrane and the pia mater
filled with cerebrospinal fluid and contains the large blood vessels that supply the brain and spinal cord
4 ventricles
third ventricle
(mid-line) cavity in the brain, bounded by the thalamus and hypothalamus on either side
fourth ventricle
extends from the aqueduct of the mid brain to the central canal of the upper end of the spinal cord;communicates by the two foramina
two lateral ventricles
communicate with the third ventricle through the interventricular foramen
epidural space
area between the dura mater and the vertebral wall,
containing fat and small blood vessels
tissues
central nervous system
peripheral nervous system.
Dendrites
responding to stimuli; they receive incoming signals towards the cell body
Schwann Cells
neuroglia cells that support neuronal function by increasing the speed of impulse propagation
neuron
cell body and one or more slender processes
neuroglia
four in central nervous system and two in the PNS
classification of neurons
bipolar neurons
two processes an axon and a dendrite
found in the retina of the eye and olfactory mucosa
uni polar neurons
a single short process that emerges from the cell body and divides T-like into proximal and distal branches
found in ganglia in the PNS ;function as sensory neurons
Multi polar neurons
three or more processes, one axon and the rest dendrites
major neurons in the CNS;common neuron in humans
major parts and function of spinal cord
nerve fibers
runs down from the brain through a canal in the center of the bones of the spine
covered by the meninges and cushioned by cerebrospinal fluid.
Spinal nerves
connect the brain with the nerves in most parts of the body
action potential
brief reversal of membrane potential;generated only in axons
Hyperpolarization: some K+ channels remain open and Na+ channels rest
Repolarization: Na+ channels are inactivating,K+ channels open
Depolarization: Na+ channels open allowing Na+ entry
resting state/voltage gated channels:all gated Na+ and K+ channels are closed
drugs that affect the brain
Cocaine and Other Stimulants
increase levels of the neurotransmitter dopamine and the hormone norepinephrine, potentially causing heart attack, overheating, and/or brain damage
Opiates and Alcohol
slow or stop breathing
increase in inhibitory effects of GABA
decrease in excitatory effects of glumate
Nicotine
reach levels high enough to paralyze the muscles that control breathing or cause a heart attack
as nicotine binds to receptors both in the brain and on muscles
rise of blood pressure ,increase of ruptured blood vessel in the brain
Compare and contrast
autonomic nervous system
varicosities and axon terminals
excitatory or inhibitory
visceral functions
smooth and cardiac muscle
endocrine and exocrine
preganglionic neuron
2 neurons
reflex arc
axons only
effectors
peripheral nervous system
acetylcholine
axon terminals
excitatory only,muscle contracts
posture and movement
skeletal muscle
somatic neuron
one neuron
Diseases associated with the brain
Dyslexia
learning disability that is neurobiological in origin; can be related to hereditary factors or other factors that affect brain development
encephalopathy
brain disease, damage, or malfunction; memory loss or subtle personality changes,dementia, seizures, coma, or death
autism
neurological and developmental disorder;troubles with social interaction and communication
microcephaly
abnormal smallness of the head; congenital condition incomplete brain development.