PLTW MEDICAL INTERVENTIONS UNIT
1.3 & 1.4 EXAM QUESTIONS AND
ANSWERS. VERIFIED 2026.
Audiogram - ANS A graphic representation of the relation of vibration frequency and the
minimum sound intensity for hearing
Cochlear Implant - ANS An electrical prosthetic device that enables individuals with
sensorineural hearing loss to recognize some sounds
Hearing Aid - ANS An electronic device usually worn by a person for amplifying sound before
it reaches the receptor organs
Inner Ear - ANS The essential part of the vertebrate organ of hearing and equilibrium that
includes the vestibule, the semicircular canals, and the cochlea
Middle Ear - ANS The intermediate portion of the ear containing a chain of three ossicles that
extends from the tympanic membrane to the oval window and transmits vibrations to the inner
ear
Outer Ear - ANS The outer visible portion of the ear that collects and directs sound waves
toward the tympanic membrane by way of a canal which extends inward through the temporal
bone
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, Sound - ANS Mechanical energy that is transmitted by longitudinal pressure waves in a
medium (water/air)
Pinna - ANS The only visible part of the ear, shaped like a funnel which assists in directing the
sound towards the middle ear
Malleus, Stapes, and Incus (Ossicles) - ANS The hammer (malleus), the anvil (incus), and the
stirrup (stapes). These bones vibrate as a result of the tympanic membrane and amplify the
vibrations to be sent into the cochlea through the oval window
Oval Window - ANS A membrane covering the entrance to the cochlea. When ossicles
vibrate, they transfer the amplified sound waves which will ripple the fluid of the cochlea (20x
pressure compared to tympanic membrane)
Semicircular Canals - ANS Three fluid-filled canals in the inner ear that help maintain balance
and equilibrium
Auditory Nerve - ANS A bundle of nerve fibers that carry information between cochlea and
the brain. Cochlea hairs connect to the auditory nerve, transmitting electrical impulses that are
later interpreted by the brain as sound
Cochlea - ANS A small, snail shell like structure that contains fluid (perilymph) and two closely
positioned membranes. These act as walls which ensure vibrations from the oval window are
transmitted to all of the fluid. The auditory hairs that line the walls convert the ripples of the
fluid from the oval window into electrical impulses sent to the brain.
Round Window - ANS A slight budge in the window of the cochlea when fluid ripples
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
1.3 & 1.4 EXAM QUESTIONS AND
ANSWERS. VERIFIED 2026.
Audiogram - ANS A graphic representation of the relation of vibration frequency and the
minimum sound intensity for hearing
Cochlear Implant - ANS An electrical prosthetic device that enables individuals with
sensorineural hearing loss to recognize some sounds
Hearing Aid - ANS An electronic device usually worn by a person for amplifying sound before
it reaches the receptor organs
Inner Ear - ANS The essential part of the vertebrate organ of hearing and equilibrium that
includes the vestibule, the semicircular canals, and the cochlea
Middle Ear - ANS The intermediate portion of the ear containing a chain of three ossicles that
extends from the tympanic membrane to the oval window and transmits vibrations to the inner
ear
Outer Ear - ANS The outer visible portion of the ear that collects and directs sound waves
toward the tympanic membrane by way of a canal which extends inward through the temporal
bone
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, Sound - ANS Mechanical energy that is transmitted by longitudinal pressure waves in a
medium (water/air)
Pinna - ANS The only visible part of the ear, shaped like a funnel which assists in directing the
sound towards the middle ear
Malleus, Stapes, and Incus (Ossicles) - ANS The hammer (malleus), the anvil (incus), and the
stirrup (stapes). These bones vibrate as a result of the tympanic membrane and amplify the
vibrations to be sent into the cochlea through the oval window
Oval Window - ANS A membrane covering the entrance to the cochlea. When ossicles
vibrate, they transfer the amplified sound waves which will ripple the fluid of the cochlea (20x
pressure compared to tympanic membrane)
Semicircular Canals - ANS Three fluid-filled canals in the inner ear that help maintain balance
and equilibrium
Auditory Nerve - ANS A bundle of nerve fibers that carry information between cochlea and
the brain. Cochlea hairs connect to the auditory nerve, transmitting electrical impulses that are
later interpreted by the brain as sound
Cochlea - ANS A small, snail shell like structure that contains fluid (perilymph) and two closely
positioned membranes. These act as walls which ensure vibrations from the oval window are
transmitted to all of the fluid. The auditory hairs that line the walls convert the ripples of the
fluid from the oval window into electrical impulses sent to the brain.
Round Window - ANS A slight budge in the window of the cochlea when fluid ripples
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
