Nervous system Flashcards
A neuron or nerve cell
The most fundamental component of the brain and nervous system.
Cell Body
The core and central structure of a neuron containing a nucleus and other specialized organelles that aid in nervous system function
Axon
The thin, tail like structure of a neuron that generates and conducts nerve impulses
Dendrites
Rootlike structures branching out of the cell body that receive and process signals from the axons of other neurons.
Neurosecretory tissues
Translate neural signals into chemical stimuli. These tissues make neurohormones, hormones produced and released by nerve cells that are released into the bloodstream
Nervous tissue
Tissue found in the brain, spinal cord, and nerves that coordinates body activities.
Neuroglia
Cells in the brain and spinal cord that form a supporting structure for the neurons and provide them with insulation
Neurosecretory tissues
Neurons that translate neural signals into chemical stimuli
Decussation
The point of crossover of the nervous system in the vertebrates located between the medulla oblongata and the spinal cord
Hypothalamus
The region at the base of the brain responsible for maintaining homeostasis
Homeostasis
A self-regulating process by which the body maintains the stability of its physiological processes for the purpose of optimal function
Sensory neurons
Nerve cells involved in communicating tactile, auditory or visual information
Motor neurons
Nerve cells that initiate muscle contraction or activate glands
Interneurons
Nerve cells that connect neurons to other neurons
Frontal lobe
The brain lobe involved in motor control, emotion, and language
Motor cortex
The region of the frontal lobe that plans and coordinates movement
Prefrontal cortex
The part of the frontal lobe responsible for high level thinking and language
Parietal lobe
The brain lobe involved in processing sensory information
Somatosensory cortex
The region of the parietal lobe responsible for processing sensations such as pain, temperature, and touch
Temporal lobe
The lateral lobe of the brain responsible for hearing, memory, and emotion
Auditory cortex
The region of the temporal lobe responsible for hearing
Occipital lobe
The posterior lobe of the brain responsible for vision
Visual cortex
The specific region of the occipital lobe responsible for sight and visual perception
Central nervous system (CNS)
The part of the nervous system consisting of the brain and spinal cord; receives sensory input and organizes, analyzes, and processes neural information.
Cerebrum
The uppermost and largest part of the brain consisting of a left and right hemisphere responsible for receiving and processing sensory information and controlling the body
Cerebellum
The region of the brain responsible for conscious motor coordination
Brain stem
The trunk of the brain, consisting of the medulla oblongata, pons and midbrain that continues downward to form the spinal cord
Cerebral cortex
The part of the brain where most neural integration occurs
Midbrain
The brain region responsible for motor movement and processing auditory and visual information
Pons
The brain region responsible for posture, facial movement, and sleep
Medulla oblongata
The base of the brain stem, responsible for involuntary functions such as swallowing, sneezing, and heart function.
Thalamus
The brain region responsible for relaying sensory and motor signals regulating consciousness
Spinal cord
The neural tissue extending from the medulla oblongata to the lumbar region (lower back) of the vertebral column that connect the body and the brain
Peripheral nervous system (PNS)
The nerves and ganglia (relay areas of neerve signals) outside of the brain and spinal cord
How are reflexes processed
Directly by the spinal cord (they do not travel to the brain)
OF what neurons PNS consist of
Afferent and efferent neurons that are responsible for communication between the body and the brain
Cranial nerves
The 12 sensory and motor nerves extending directly from the brain
Spinal nerves
Bundles of nerves connected to the spinal cord carrying information toward periphery
Efferent neurons (motor neurons)
Carry signals from the CNS to the muscles to generate movement
Somatic nervous system
The part of the nervous system controlling voluntary movement
Atonomic nervous system
The part of the nervous system responsible for involuntary functions and movement
Sympathetic nervous sytem
The autonomic system responsible for fight or flight
Parasympathetic nervous system
The autonomic system responsible for rest and digest
Internal stimuli
Sensory input form within the body
External stimuli
Sensory input from exterrnal sources
Mechanoreceptors
Nervous system receptors responding to mechanical stimuli such as sound or touch
Tactile receptors ( part of Mechanoreceptors)
Collect and communicate sensations of touch
Proprioceptors ( part of Mechanoreceptors)
Communicate the position of the body and movement
Baroreceptors ( part of Mechanoreceptors)
Collect and communicate changes in blood pressure
Proprioception
Perception or awareness of body movement or position in space
Myelin sheath
The insulation of neuron axons made of proteins and fats, which propagates neural impulses
Nerve impulses
The electrical signals used for nerve communication
Sensory integration
The way the brain works to affect responses to neural input
Motor function
Includes both voluntary and involuntary muscle contractions
Motor unit
A single motor neuron and the muscle fibers it controls
Motor unit pool
A group of motor units that work together
Extrafusal muscle fibers
Fibers that cause muscle contraction and mechanical work
Alpha motor neurons
Motor neurons originating in the brain stem and spinal cord that initiate muscle contraction
Excitation-contraction coupling
The physiological process of converting a neural impulse into a mechanical response
Action potential
An exposion of electrical activity caused by a neural impulse
All-or-none principle
The principle stating the strenght of a neural electrical signal is independent of the magnitude of the stimulus so long as the neural threshold is achieved
