what are the two types of nervous system
What allows communication in the brain?
The corpus callosum
what are the 2 large hemispheres connected by?
The corpus callosum
What is the cerebral cortex?
Thin, gray matter layer on surface of brain that goes in and out of the grooves.
Arachnoid
Thin, net-like membrane
Bipolar
Two nerve fibers, one dendrite , one axon
Interneuron
directs response to muscles that pull away injured part and also deadens anatagonist muscles.
functions of temporal lobe ?
interpretation of auditory and olfactory sensations
Insula
interpretation of taste, emotions and self awareness
Somatosensory
interpreting sensory information for skin
Neurilemma
is the outer layer of the Schwann cell containing the nucleus & cytoplasm. Not continues-has neurofibril notes (nodes of Ranvier)
Multipolar
many dendrites, one axon
What is a nerve composed of?
many neurons +ct +blood vessels
Unipolar
one nerve fiber that divides into one dendrite portion and axon portion
Dendrites
process that receive information stimuli
converting circuit
several neurons send impulses to fewer. ex: rods in our eyes, production of saliva
what is under the cerebral cortex?
white matter, myelinated neurons that act as thought freeways (tracts)
Nissl
(chromatophilic substance ) made of ribosomal RNA and rough ER in the cell body
What are some examples of involuntary Actions ?
-Heart rate -Breathing rate -Blood pressure -Digestion
What are the different types of reflexes?
-Involuntary Actions -Automatic Actions -Stretching reflex -Withdrawal Reflex
Functions of frontal lobe ?
-intellectual functions(reasoning , planning) -personality(phineas coage) -verbal communication (motor speech area (broca's area) controls muscular movements for taking ) -primary motor cortex in the precentral gyrus -neurons send impulses to voluntary muscles
what is a neuron?
A nerve cell
ependymal cells
Lines inside of brain ventricles
What is Myelination accomplished by in the CNS
Oligodendrocytes
diverting circuit
One (few) neuron(s) send impulses to many. Ex: brain to walking muscles.
Dura Mater
Outermost, tough, fibrous ct
what are the 2 types of myelinated tracts
-Ascending tracts -Descending tracts
What are the different types of Glial Cells ?
-Astrocytes -Ependymal cells -Microglia -Oligodendrocytes
What are the functions of the cavities of the brain?
-Brings nutrients to an takes away wastes from the brain cells. -protection
what are the different type of membranes of brain and spinal cord?
-Dura Mater -Arachnoid -Pia mater
Advantages of the myelin sheath
-Electrically insulate the neuron -Increases the speed of the neuron (200x) by saltory conduction
Neuron Classification
-Unipolar -Bipolar -Multipolar
what are is the structure of a neuron?
-cell body -Nissl bodies -Dendrites -Axon
what are some examples of automatic Actions
-coughing -sneezing -swallowing -vomiting
What does the peripheral nervous system consist of?
-cranial nerves -spinal nerves -ganglia
what does the surface of the brain contains?
-gyri(gyrus)-folds -sulci (sulcus)-grooves
functions of parietal lobe ?
-primary somatosensory cortex (in postcentral gyrus ) senses skin's touch , pain , temperature -Wernickes area-understanding speech and formulating words
characteristic of spinal cord
-spinal cord enclosed within the vertebral canal -spinal cord has spinal nerves exiting sides -A typical adult spinal cord ranges 16 to 18 inches in length -the lumber and sacral part divides into groups of axons called the cauda equina
Gray matter
-unmyelinated -its shape resembles a letter H or a butterfly
what are some examples of stretching reflex?
-we trick our bodies into thinking we are falling over backward -no interneuron
Characteristics of Schwann cells
-wrap around axon 100 x times -About 1 mm long -Composed of myelin -sometimes this is called the myelin sheath
Oligodendrocytes
Myelinates neurons in the CNS
What is Myelination accomplished by in the PNS?
Schwann cells (neurolemmocytes)
what is the average weight of an adult brain?
around 3 pounds
What does the central nervous system (CNS) consist of?
brain and spinal cord
withdrawal reflexes
caused by pain stimulus example: flame/heat, stepping on a track
what are the two types of nervous system?
central nervous system (CNS) and Peripheral nervous system (PNS)
What provides for a larger surface area for neuron dendrites, cell bodies and unmyl, neurons?
cerebral cortex
what are the cavities in the brain filled with ?
cerebrospinal fluid
Gnostic area(Common integrative area)
combines sensory, visual and auditory information
What are the functions of the corpus callosum?
connects halves and allows communication.
Association areas
connects sensory and motor "cortical" areas in all areas of the brain
Cell body
control center for receiving, integrating (processing) and sending nerve impulses.
interprets incoming
coordinates response
Pia Mater
delicate, loose ct, nourishes cells of brain and spinal cord (ceramic wrap)
neurons
excitable cells that initiate and transmit nerve impulses
Visual
face or place recognizing feelings
What are Schwann cells needed for ?
for regeneration
How many cavities are in the brain
four
somatic sensory
input received from body (eyes, ears, skin)
visceral sensory
input received from internal organs
what enhance cognitive processes ?
more neural connections
Auditory
music-memories happy or sad
what are Oligodendrocytes needed for in the CNS?
myelin production
white matter
myelinated tracts
what are the two different type of cells that form the nervous tissue?
neurons and glial
Do all axons have myelin sheath?
no
Does regeneration occurs in the CNS?
no
Glial cell
non-excitable cells that support and protect the neurons
what determines the intelligence ?
number of active synapses
autonomic motor
output transmitted to involuntary muscles (cardiac, smooth) and glands.
somatic nervous
output transmitted to skeletal muscles
microglial cells
phagocytizes pathogens and cellular debris
Axon
process that transmits impulses away from cell body
Higher order processing centers
processes several association areas for complex thought processing involving speech, cognition (awareness, knowledge, memory). understanding spatial relaships. ex word problems
what is meninges?
protective membranes that cover the brain and spinal cord
Pre-motor cortex ( somatic motor)
reading a book, playing a piano
Sensory division
receives sensory information from receptors and transmit this information to the CNS
Wernike's
recognizing, understanding, comprehending, spoken/ written language
Interneurons (association)
relay neurons which exist within the CNS
What are the different types of neurons ?
sensory neurons, interneurons, motor neurons
What are neurons organized into?
specific pathways
Astrocytes
structural support & helps from blood-brain barrier
What are the parts of the Diencephalon ?
thalamus, hypothalamus, epithalamus
descending tracts
transmit down motor information
ascending tracts
transmit up sensory information
motor neurons(efferent)
transmits impulses from CNS to effectors .
Sensory Neurons (afferent)
transmits impulses from receptors to CNS
motor division
transmits motor impulses from the CNS to the muscles or glands.
How many distinct cell types are in the nervous tissue
two
functions of occipital lobe
vision
What is saltatory conduction ?
when the impulse leaps from one neurofibril node to another neurofibril node instead of moving heel to toe along the entire axon.
