Peripheral Nervous System (Ch. 13)
Division that controls voluntary skeletal muscle movement using a single neuron pathway
Somatic motor division
Most visceral organs receive input from both sympathetic and parasympathetic divisions
Dual innervation
Process by which light energy is converted into electrical signals in the retina
Phototransduction
Condition where blocked aqueous humor drainage increases intraocular pressure and damages optic nerve
Glaucoma
Mechanism that stabilizes internal conditions by reversing the original stimulus
Negative feedback
A nerve that contains both sensory (afferent) and motor (efferent) fibers
Mixed nerve
State in which heart rate increases, pupils dilate, and digestion decreases
Sympathetic dominance
Reason a person walking from a dark room into bright sunlight initially experiences temporary blindness
Rods saturation
Disorder causing loss of central vision due to deterioration of macula lutea
Macular degeneration
Condition in which a cell shrinks due to water leaving via osmosis
Hypertonic solution
Condition that would most likely cause inability to extend the wrist (“wrist drop”)
Radial nerve injury
State in which digestion increases and heart rate slows
Parasympathetic dominance
Region of the retina with highest visual acuity due to dense cone concentration
Fovea centralis
Condition where neural retina separates from pigmented layer, risking blindness
Detached retina
Tissue best suited for protection against abrasion (e.g., epidermis)
Stratified squamous epithelium
Clinical tool used to determine spinal nerve damage based on sensory loss patterns
Dermatome mapping
Structural feature of ANS pathways involving preganglionic and postganglionic neurons
Two-neuron chain
Hearing loss caused by damage to inner ear structures or auditory nerve
Sensorineural deafness
Condition where focal point is in front of retina due to elongated eyeball
Myopia
Cell responsible for bone resorption during remodeling
Osteoclast
Neural pathway that produces a rapid, involuntary response without conscious brain involvement
Reflex arc
Receptors that bind norepinephrine or epinephrine during sympathetic responses
Adrenergic receptors
Mechanism that stimulates hair cells in semicircular ducts to detect rotational motion
Endolymph movement
Hearing loss due to impaired transmission of sound waves through middle ear
Conduction deafness
Cause of movement disorders such as Parkinson’s disease due to impaired motor regulation
Basal nuclei dysfunction