Nervous System Flashcards
Roles of NS
Sensing
Integrating
Responding
What does CNS consist of
Brain and spinal cord
What does PNS consist of
Sensory and motor
Sensory (afferent)
Carries signals from the nerve endings to the CNS
Motor (efferent)
Division transmits information from the CNS to the rest of the body
Four type of neuralgia in the CNS
Oligondendocytes
Ependymal xells
Microglia
Astrocytes
Olingodendeocytes
Form the myelin sheikh in the brain and spinal cord
(Oligo=few)
Ependymal cells
Line the spinal cord and cavities of the brain
Microglia
Perform phagocytosis of micro-organisms and cellular debris
Astrocytes
Nourish neurons in the brain tissue
Neuroglia in the PNS
Schwann cells
Satellite cells
Schwann cells
Form the myelin sheath around nerves in the PNS
Satellite cells
Nourish the neurons
Classes of neurons
Sensory neurons
Interneurons
Motor neurons
Sensory neurons (afferent)
Detect stimuli and transmit information to the CNS
Interneurons
Connect incoming sensory pathways with outgoing motor pathways
Motor neurons (efferent)
Relay messages from the brain to the muscle or gland cells
Neuron structure
Soma
Dendrites
Axon
Myelin sheath
Nodes of ranvier
Synaptic knob
Soma
The cell body
Control center that contains the nucleus
Dendrites
Received signals from the other neurons and send the info to the stoma
Axon
Carry signals w away from the soma
Myelin sheath
Insulates the axon
Nodes of ranvier
Gaps in the myelin sheath that assist with conduction of impulse
Synaptic knob
Neurotransmitter- containing vesicles at the end of the axon branches
Those of neurons
Multipolar neurons
Bipolar neurons
Unipolar neurons
What role does the sodium potassium pump play in the nervous system ?
Is it part of the nerve transmission process
Impulse conduction
- Resting potential
- Depolarization
- Action potential
- Repolarization
- Refractory period
Resting potential
Outside the cell
Na+; inside = K+ and negative ions
Depolarization
Stimulus causes Ana+ to enter cell
Action potential
Stimulus goes above the threshold level
Channels open and more Na+ enters the cell
Repolarization
K+ flows out of the cell; electrical balance is restored
Na+ and K+ are now in the wrong side
Refractory period
Sodium potsssium pump works to return Na+ and K+ to correct side
Synapses
Electrical synapse
Chemical synapse
Electrical synapse
The neurons touch which allows an action potential to pass directly from one neuron to the next
Chemical synapse
The neurons do not touch so neurotransmitters are used to cross the synaptic cleft and carry the message from the pre synaptic neuron to the postsynaptic neuron
Parts of spinal cord
Cauda equina
Ascending tract
Descending tract
Cuada equina
Bundle of nerve roots that protrude from the end of the spinal cord
Ascending tract
Conveys sensory signals up the spinal cord
Descending tract
Conveys impulses down the spinal cord to the skeletal muscles
Gray matter vs white matter
Gray matter contains no myelin
White matter contains myelin
What does gray matter contain
Contains motor neurons and Interneurons
What does white matter contain
Contains bundles of axons that carry impulses away from one part of the nerve system to another
Contains
Epidural space
Area between the dura matter
Contains blood vessels, connective tissue and fat
Contains cerebrospinal fluid
Meningeal layer
Pia matter (inner most layer, contains blood vessels)
Arachnoid matter (middle layer, thin)
Dura matter (outer layer, tough)
How many cervical nerves
8
How many thoracic nerves
12
How many lumbar nerves
5
How many sacral nerves
5
How many cocygeal nerves
1
How many pairs of spinal nerves?
31
4 major regions of the brain
Cerebrum
Diencephalon
Cerebellum
Brain stem
What are gyri and sulci
Gyri; ridges of the brain
Sluci; grooves of the brain
Diencephalon
Between the cerebrum and the midbrain
Components of the brain stem
Mid brain
Pons
Medulla oblagonta
Longitudinal fissure
Feel groove that divides the cerebrum into left and right hemispheres.
Corpus callosum
Bundle of nerves that connect the left and right hemisphere
Where in the brain do you find gray matter
Surface of the brain (covering the cerebrum and cerebellum)
In patches (nuclei) in the white matter
Where in the brain do you find white matter
Underneath the cerebral cortex
Two layers of the dura matter
Periosteal layer (attached to inside the skull)
Meningeal layer (covers the brain)
Diesel sinuses
Spaces in the dura matter than collects blood that has passed through the brain and needs to be returned to the heart
Subdural space
Separates the dura matter from the arachnoid mater
Subarachnoid space
Separates the arachnoid mater from the pia mater
Role of the midbrain
Contains tracts that relay sensory and motor impulses
Contains centres for auditory and visual reflexes
Contains clusters of neurons integral to muscle control
Role of pons
Contains tracts that convey signals to and from different parts of the brain
Major centres of the medulla oblagonta
Cardiac center
Vasomotor center
Two respiratory centres
Roles of cerebellum
Monitors the body movements
Sends messages for balance, coordination and posture
Stores the info needed for muscle groups ti work together in coordinated movement
Evaluates sensory input (touch, sound)
Roles of thalamus in the Diencephalon
Processes sensory inputs and decides which ones to transmit to the cerebral cortex
Involved in memory and emotion
Roles of hypothalamus in the Diencephalon
Controls the autonomic nervous system
Contains centres for hunger, thirst; and temperature regulation
Controls the pituitary gland
Play a role in many emotional responses (anger, fear, pleasure..)
What does the front lobe control?
Voluntary movements
Memory
Emotion
Social judgment
Decision making
Reasoning
Aggression
Certain personality aspects
What does the temporal lobe control?
Hearing
Smell
Learning
Memory
Emotional behaviour
Visual recognition
What does the parietal lobe control?
Relieving and interpreting bodily sensations (touch, temp, pressure, pain)
Awareness of one’s body and body parts in space and relation to eachother m
What does occipital lobe control?
Vision
Visual information
What does the insular lobe control
Perception
Motor control
Self awareness
Cognitive functioning
Two key structures of limbic system
Hippocampus
Amygdala
Hippocampus
Converts short term memory into long term memory
Amygdala
Stores and recalls emotions from past events
Emotions, jealousy, anger
Nerve I & function
Olfactory nerve
Sense of smell
Nerve II & function
Optic nerve
Vision
Nerve III & function
Oculomotor nerve
Pupil constriction and voluntary eye movements
Nerve IV & function
Trochlear nerve
Eye movements
Nerve V & functions
Trigeminal nerve
Touch, temp, pain on face
Also controls, chewing and detects lower jaw sensations
Nerve VII & function
Facial nerve
Taste , facial expression, and secretion of tears and saliva
Nerve VIII & function
Vestibulochochlear nerve
Hearing and balance
Nerve IX & function
Glossopharyngeal nerve
Tounge movement, sensation
Also plays a role in blood pressure regulation
Nerve X & function
Vagus nerve
Many heart, lung, digestion and urinary functions
Nerve XI & function
Spinal accessory nerve
Movement of the head, neck and shoulders
Nerve XII & function
Hypoglossal nerve
Tounge movement
