Chapter 9 Flashcards
3 parts of a neuron
Cell body, dendrites, axon
Nerve cells
Neurons
Bundle of axons
Nerve
Supporting cells
Neuroglial cells
What is each nervous system? 2
Central nervous system-brain and spinal cord
Peripheral nervous system-nerves
Name the general functions of nervous system
Sensory function
Integrated function
Motor function
Name functions of neuroglial cells
Carry phagocytosis Provide insulating layers of myelin Provide structural support and fills spaces Covers and forms inner linings Forms myelin sheath
Name neurons classification on basis of structure
Bipolar
Unipolar
Multipolar
Classification on basis of function
Sensory neuron
Interneuron
Motor neuron
Define resting potential
In a resting nerve cell, the potential difference between inside and outside of cell membrane (-70 mv)
When resting potential becomes more positive
Depolarized
Explain ion movement that makes action potential
@ threshold, NA ions diffuse inward, Depolarizes the membrane
@ same time, K ions diffuse outward, repolarize the membrane
Rapid change in potential (+30 mv)
Action potential
Wave of action potential
Nerve impulse
Differentiate conduct impulses
Un myelinated axons conduct impulses over entire surface
Myelinated axons conduct impulses faster because they jump from node to node
Junction between two neurons
Synapse
Groups of neurons that make 100s of synaptic connections to perform a common function
Neuronal pools
Neuron receives subthreshold stimuli and becomes more excitable to incoming stimuli
Facilitation
Differ between convergence and divergence
Convergence-impulses from 2 or more incoming axons may converge on a single neuron
Divergence- impulse from 1 axon that may diverge by passing into several output neurons
Simple pathway that includes only a few neurons
Reflex arc
What is reflex behavior
Automatic, subconscious responses to changes inside or outside the body
Membranes surrounding and protecting brain and spinal cord
Meninges
Name the 3 layers in meninges
Dura mater
Arachnoid
Pia mater
4 characteristics of spinal cord
31 segments
Cervical enlargement
Lumbar enlargement
Deep anterior groove and shallow posterior grooves extends length of spinal cord
Where is the gray and white located in the spine
A central core of gray matter surrounded by white matter
Functions of spinal cord
Provides 2-way communication systems between brain and rest of body
Center for spinal reflexes
Ridges on the surface
Convolutions (gyri)
Shallow groove
Sulcus
Deep groove
Fissure
Name the lobes of the brain
Frontal, parietal, temporal, occipital
Thin layer of gray matter on surface, contains 75% of all neuron cell bodies in nervous system
Cerebral cortex
Compare grey and white on brain and spinal cord
Brain-white matter makes up bulk of cerebrum
Spinal cord-central core of gray matter surrounded by white
Function of cerebrum
Provides highs brain functions:memory, reasoning, intelligence, personality
Function of olfactory bulb
Responsible for sense of smell
Interconnected cavities within hemispheres and brain stem
Ventricles
Function of cerebrospinal fluid
Protects brain and spinal cord by absorbing shock,
Maintains stable ionic concentration and
Provides pathway to the blood for wastes
Function of thalamus
Central relay station for incoming sensory impulses
Function of hypothalamus
Maintains homeostasis
Function of midbrain
Reflex centers associated w eye,ear, and head movements
Function of pons
Transmit impulses (cerebrum to other parts of nervous system) and regulates rate and depth of breathing
Function of medulla oblongata
Centers for cardiac, vasomotor, respiratory, coughing, sneezing, swallowing, vomiting
Filters incoming sensory impulses arousing cerebral cortex into wakefulness when significant impulses are received
Reticular formation
Function for cerebellum
Reflex center in coordination of skeletal muscle movements and maintenance of equilibrium and maintains posture
