C11: Nervous System Flashcards
Memorize
What are the 5 lobes of the cerebral cortex?
Occipital, temporal, parietal, frontal, and insula
What is the role of the temporal lobe?
Governs hearing, smell, learning, memory, emotional behavior, and visual recognition
What is the role of the front lobe?
Governs voluntary movements, memory, emotion, social judgment, decision making, reasoning, and aggression; also the site for certain aspects of one’s personality
What is the role of the parietal lobe?
Receiving and interpreting bodily sensations (touch, temp, pressure, and pain), and governs proprioception
What is the role of the occipital lobe?
Analyzing and interpreting visual information
What is the role of the insula?
Perception of pain, basic emotions (joy, happiness, anger, and disgust), addiction, motor control, self awareness, and cognitive function
What is resting potential?
The state of being inactive and polarized, waiting for a stimulus to come along so it can react
What are the components of a neuron while in resting potential?
Positive charges of sodium on the outside and negative potassium charges on the inside. The two ions leak across the membrane due to its permeability, but the sodium potassium pump constantly restores the ions to the appropriate sides
What is membrane potential?
Ions if opposite charges separated by a membrane, with the potential to move inward to each other depending on the permeability of the membrane. It is polarized.
What happens to the neuron when a stimulus comes along?
Channels on the resting neurons membrane open and sodium ions from outside rush inside, changing the inside charge to positive, becoming depolarized
What happens is depolarization is strong?
More channels along the neurons membrane open, allowing more sodium ions in, creating an action potential
What is an action potential?
The neuron has become active as it conducts an impulse along the axon (meaning nerve impulse)
What happens during repolarization?
The influx of sodium causes other channels to open along the neuron membrane that allow potassium outside. The sodium channels begin to shut, this causes the ions to be flip flopped.
What happens during the refactory period?
The membrane is polarized but won’t respond to anymore stimuli until the ions are on the correct side of the membrane, so the sodium potassium pump works to return the ions to the correct sides, making the neuron polarized and in resting potential.
What is/How does the sodium potassium pump?
It’s a channel protein that has receptor sites. It allows 3 sodium ions from inside the cell attach to the receptor site, it then gets fueled by ATP to open up to the outside of the cell to release the sodium ions, and then 2 potassium ions from the outside can attach to the receptor sites and brought back into the inside of the cell. Return concentration levels within normal limits
What is the role of the cerebellum?
Plays a role in motor functions (body movement, balance, coordination, posture), sensory, cognitive, and emotional functions.
What is the role of the hypothalamus?
Controls autonomic nervous system.
Responsible for, hunger, thirst, and temp regulation
Called the master gland b/c it controls the pituitary gland
Involved in multiple emotional responses
What are the meninges of the CNS?
Dura, arachnoid, and pia
What is the difference between PNS and CNS?
PNS: nerves throughout the body
CNS: only the brain and spinal cord
What are the 2 subdivisions of the PNS ans their functions?
Sensory (afferent) division: carries signals from nerve endings to CNS
Motor (efferent) division: transmits information from CNS to the rest of the body
What is the subdivisions and their functions of the afferent division of the PNS?
Somatic sensory: caries signals from skin, bones, joint, and muscles
Visceral sensory: caries signals from viscera of heart, lungs, stomach, and bladder
What is the 2 subdivisions and their functions of the efferent division of the PNS?
Somatic motor: allows voluntary movements of skeletal muscle
Autonomic motor: provides “automatic” activities such as control of BP and heart rate
What is the sympathetic vs parasympathetic divisions of the PNS?
Sympathetic: arouses the body for action
Parasympathetic: has a calming effect
What are 2 functions of the spinal cord?
Relays info to and from the brain
Reflexes
What is the thalamus?
Filters and transmits some impulses like smell, sight, taste, pain, pressure, heat, cold, and touch to the cerbral cortex
How does the brain protect itself?
Meninges, ventricles, cerebrospinal fluid, and the blood-brain barrier
What is cerebrospinal fluid?
Provides nourishment of glucose and protein, removes metabolic waste, and cushions the brain against minor trauma
What structure secretes CSF and where is it located?
The choroid plexus and its found in each lateral ventricle
What are the ventricles of the brain?
Two lateral ventricles on each side of the hemisphere that connect to the 3rd ventricle, and a canal leads it to the 4th ventricle
What is the flow of CSF?
Choroid plexus in each lateral ventricle secretes CSF, it flows into the 3rd ventricle where the choroid plexus adds more CSF that flows into the 4th ventricle, where even more CSF is added. Some of the CSF flow through foramina (two tiny openings) into the subarachnoid space, up the back of the brain, down the spinal cord, and up the front of the brain
What is the blood-brain barrier?
A membrane that is high selective in what passes between the blood plasma and extracellular fluid of the brain, keeping harmful substances out and allowing important substances in
What is the difference between grey and white matter?
Grey matter: it’s unmyelinated neurons in the CNS. Higher functions like integration, decision-making, and voluntary control happen here
White matter: is white b/c the neurons are myelinated
What is the structure of a neuron?
Dendrite, body, and axon
What are the 3 types of neurons?
Afferent (sensory)
Interneuron (autonomic)
Efferent (motor)
What are neuroglial cells?
Microglial: phagocytosis and lines important organs to prevent infection
Oligodendrocytes & Schwann cells: make myelin sheath
Astrocytes: structure and support
Ependymal: lines cavities, secretes and absorbs CSF
What is the function of the olfactory nerve?
Smell
What is the function of the optic nerve?
Sight
What is the function of the trigeminal and facial nerve?
Skin and muscles of the face
What is the function of the vestibulocochlear nerve?
Equilibrium and hearing
What is the function of the vagus nerve?
Primary role in the parasympathetic system for digestion and breathing
What are the difference between sympathetic and parasympathetic functions, fibers and secretions?
Sympathetic:
- flight or fight response. Heightened awareness and stress
- SHORT presynaptic fibers secret AcH
- LONG postsynaptic fibers secret norepinephrine
- rises from thoracic and lumbar area
Parasympathetic:
- relaxes
- LONG presynaptic fibers secret AcH
- SHORT postsynaptic fibers secret AcH
- rises from brain stem and sacrum
