Among the different parts of the ear, which of the following parts is called the organ of hearing?

NHM UP Staff Nurse-2023 Shift-2nd

Applied Anatomy

Easy

Appeared in: NHM UP Staff Nurse-2023 Shift-2nd

Explanation

The Organ of Corti is the specialized sensory organ for hearing, located within the cochlea of the inner ear.
It rests on the basilar membrane and contains thousands of mechanoreceptor cells known as hair cells.
These hair cells transduce the mechanical energy from sound vibrations (transmitted through the ear ossicles and cochlear fluid) into electrical signals.
The electrical signals are then transmitted to the brain via the cochlear division of the vestibulocochlear nerve (CN VIII), where they are perceived as sound.

Option B: Cristae (specifically, cristae ampullaris) are sensory organs located in the ampullae of the semicircular canals. They are responsible for detecting rotational or angular movements of the head, which is part of the system for dynamic equilibrium (balance), not hearing.
Option C: The macula is a sensory receptor found in the utricle and saccule of the inner ear's vestibule. It detects linear acceleration and the position of the head relative to gravity, contributing to static equilibrium (balance), not hearing.
Option D: The Malleus, also known as the hammer, is one of the three small bones (ossicles) in the middle ear. Its function is to transmit and amplify sound vibrations from the tympanic membrane (eardrum) to the incus. It is part of the conductive pathway for sound, not the sensory organ where sound is transduced into nerve signals.

Clinical Relevance

Nursing practice connection: Knowing Anatomy and physiology of the ear, specifically identifying the organ of hearing helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Understanding the function of the Organ of Corti is fundamental to comprehending sensorineural hearing loss, which occurs when the delicate hair cells are damaged by factors like loud noise, ototoxic drugs, or aging.
A nurse's assessment of a patient reporting dizziness (vertigo) versus hearing loss requires differentiating between the vestibular system (Cristae, Macula) and the auditory system (Organ of Corti).
What if? If a patient has damage to the cristae and maculae but their Organ of Corti is intact, they would experience severe vertigo and balance issues, but their hearing would likely remain normal.

How to Approach the Question

First, identify the core concept of the question, which is the specific 'organ of hearing'.
Recall the three main parts of the ear: outer, middle, and inner. The outer and middle ear are primarily for sound conduction, while the inner ear houses the sensory organs for both hearing and balance.
Evaluate each option based on its location and function.
Eliminate Malleus, as it is a bone in the middle ear responsible for sound transmission, not sensory reception.
Differentiate the functions of the inner ear structures. Recall that the cochlea is for hearing, while the vestibule and semicircular canals are for balance.
This allows you to eliminate Cristae and Macula, which are balance receptors.

Concept Tested & Keywords

Concept Tested: Anatomy and physiology of the ear, specifically identifying the organ of hearing.
Stem keywords: ear, organ of hearing
Lead-in keywords: which of the following

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