Nervous System Flashcards
Neuron
The functional unit of the nervous system, a specialized cell that receives information and transmits it to other cells
Dendrite
A branch-like structure that functions by receiving messages from other neurons and allow the transmission of messages to the cell body
Soma
Cell body with a nucleus
Myelin Sheath
insulate the axon to increase the speed of nerve impulse transmission
Axon
tube-like structure that carries an electrical impulse form the cell body to the axon terminals for passing the impulse to another neuron
Axon Terminal
a bulb like structure on the end of neurons that releases neurotransmitters to transmit signals to other cells
Neuroglia
non-neuronal cells that support and protect the neurons, facilitates the functioning of the communications network
Node of Ranvier
electrical signals occur at gaps in the myelin sheath which speeds the conduction of nerve impulses down the axon
Neurotransmission
two or more neurons communicating with each other
Synapse
allows a neuron to move an electrical or chemical signal from one neuron to another neuron
PNS
peripheral nervous system, nerves outside the brain and spinal cord
CNS
central nervous system, includes the brain and spinal cord
Satellite Cells
provide structural and metabolic support to neurons
Schwann Cell
insulate neurons with the myelin sheath in the PNS
Oligodendrocytes
insulate multiple neurons with myelin sheath in the CNS
Major Lobes of the Cerebrum
Frontal, parietal, temporal and occipital
Cerebrum
wrinkly part of the brain that hold conscious thoughts, meaning, and language
Cerebellum
also called the little brain, is responsible for coordinating movement, balance and posture
Midbrain
controls some motor movements, vision, hearing and the sleep/wake cycle. Found deep to the cerebrum
Brainstem
connects the brain to the spinal cord
Somatic Nervous System
branch of the PNS that controls voluntary movement and sensory input
Autonomic Nervous System
branch of the PNS that controls involuntary movements and bodily functions such as breathing and digestion.
Sympathetic Nervous System
responsible for fight, flight or freeze responses, increased heart rate, blood pressure and breathing rate.
Parasympathetic Nervous System
Rest and digest response, relaxes the body after stressful or dangerous situations, increases digestion, slows heart rate and slows breathing.
Astrocytes
A glial cell that clears excess neurotransmitters, and regulates the blood brain barrier
Depolarization
the electrical impulse caused by a stimulus that moves down the axon, the movement of ions across the cell membrane through voltage gated channels (sodium in, potassium out)
Voltage gated channels
channels in the cell membrane of a neuron that are opened by two like-charged ions bonding to the channel, the repelling forces cause the channel to open
Vesicles
A transporting organelle containing neurotransmitters that are released into the synapse at the terminal buttons of a neuron
neurotransmitters
chemical messengers released from the terminal buttons of one neuron into the synapse that trigger the depolarization of the other neuron in the synapse
synaptic gap (synaptic cleft)
the small space between neurons where neurotransmitters are released, found between the terminal buttons of one neuron and the dendrites of the another neuron
Acetylcholine (ACh)
the most common neurotransmitter, located in both the CNS and PNS , regulates many body functions including cardiac contractions, blood pressure, and intestinal peristalsis
Dopamine
a neurotransmitter involved in regulating motor activity, mood, sensory perceptions, and attention
Glutamate
excitatory neurotransmitter involved in learning and memory
Epinephrine
aka adrenaline, activates “fight or flight” in the autonomic nervous system
Serotonin
neurotransmitter involved in complex cognitive functions (sleep, eating, etc), found in the brain, stomach and spinal cord.
GABA
a inhibitory neurotransmitter the stops the brain from becoming over excited
Cranial Nerves
set of 12 nerves that send electrical signals to the brain, head, face, neck and torso. Control 5 senses, smell, sight, taste, hearing, movement of facial muscles
Olfactory nerve
CN I, provides sense of smell
Optic Nerve
CN II, provides vision
Oculomotor nerve
CN III, opening and moving your eyes, adjusting pupil width
Trochlear Nerve
CN IV, looking down, moving your eyes toward or away from your nose
Trigeminal Nerve
CV V, providing sensations in your eyes, most of your face and inside your mouth, allows you to chew food
Abducens Nerve
CN VI, moving your eyes from left to right
Facial Nerve
CN VII, Controls several facial muscles to make facial expressions and providing a sense of taste in part of your tongue
Vestibulocochlear Nerve
CN VIII, Provide sense of hearing and balance
Glossopharyngeal Nerve
CN IX, providing taste sensations to part of your tongue and controlling muscles for swallowing, blood pressure and saliva production
Vagus Nerve
CN X, regulate digestion, blood pressure, heart rate, breathing, mood, saliva production and more. Main nerve of Parasympathetic nervous system
Accessory Nerve
CN XI, controlling shoulder and neck movement
Hypoglossal nerve
CN XII, controls tongue movement
Grey Matter
Primarily composed of neuron somas, darker outer portion of the brain
White Matter
primarily made of axons, lighter inner portion of the brain
Cerebrum
wrinkly outermost portion of the brain, initiates and coordinated movements, regulates temperature, speech, thinking, reasoning and special senses
Cerebellum
“little brain”, coordinates voluntary movement, maintain posture, balance and equilibrium.
Brainstem
connects the cerebrum to the spinal cord, contains pons, midbrain and medulla
Midbrain
part of the brainstem responsible for hearing, movement, and responses to environmental changes
Pons
Part of the brainstem that acts as the connection between midbrain and medulla, responsible for chewing, blinking, facial expression and more
Medulla
Bottom of the brainstem, essential for survival, responsible for heart rhythm, breathing, blood flow, oxygen and carbon dioxide levels
Spinal Cord
carries messages to and from the brain and the rest of the body
Meninges
three protective coverings around the brain and spinal cord
Dura Mater
outermost protective layer, thick and tough
Arachnoid Mater
thin middle layer of meninges, does not contain nerves or blood vessels, web like structure
Pia Mater
thin innermost layer of meninges, contains blood vessels
Frontal Lobe
Main center for personality, decision making, movement, speech and more. Anterior most part of the brain, contains Broca’s area
Parietal Lobe
Involved in spatial awareness, identify objects, interpreting pain and touch, contains Wernicke’s area
Occipital Lobe
Responsible for interpreting vision
Temporal lobe
Involved in speech, short term memory, and musical rhythm
Pituitary Gland
pea sized structure deep in the brain superior to the nose, regulates hormones from thyroid, sex glands and adrenal glands of the kidney
Hypothalamus
controls the chemical messages that regulate the pituitary gland, regulates body temperature, sleep patterns, hunger, and thirst
Amygdala
regulates emotion and memory and are associate with the brain’s reward system, fight or flight response and stress
Hippocampus
Involved in memory, learning, navigation, and perception of space
Pineal gland
Regulates sleep and wake cycles through the response of light and dark, releases melatonin
Cerebrospinal Fluid
aka CSF, watery fluid that circulates around the brain and spinal cord, washes the CNS to remove impurities and deliver nutrients
Prefrontal Cortex
The personality center of the brain unique to humans in the frontal lobe of the brain
