Problem 89 - Objective Biology for NEET

Question

Malleus is a part of (a) Fore limbs of vertebrates (b) Reproductive organs of cockroach (c) Auditory ossicles of middle ear of human (d) Skull of frog

Step-by-Step Solution

Answer

The correct answer is (c) Auditory ossicles of middle ear of human.

Step 1: Identify the Malleus

Malleus is an auditory ossicle, meaning it is a bone located in the middle ear. Auditory ossicles are parts of the hearing mechanism in mammals.

Step 2: Compare with Options

Compare this information with the options provided. The malleus is not part of the fore limbs of vertebrates (option a), the reproductive organs of a cockroach (option b), or the skull of a frog (option d).

Step 3: Choose the Correct Option

From the comparison made in step 2, it is clear that the malleus belongs to the auditory ossicles of the middle ear of a human, which is option c.

Key Concepts

Malleus

The malleus is one of the tiny bones located in the middle ear of humans and other mammals. Commonly referred to as the "hammer," it is named for its distinct shape, resembling a tiny hammer. This bone is one of three auditory ossicles that play a crucial role in hearing.

• The malleus connects to the tympanic membrane, also known as the eardrum.
• It receives vibrations from the eardrum when sound waves enter the ear.
• These vibrations are then transmitted to the incus, another ossicle. This transmission is essential for hearing, as it continues the chain that sends sound to the inner ear.

The movement of these bones is responsible for amplifying sound, making it possible for us to perceive different pitches and volumes. Understanding the malleus’s role is fundamental to grasping the process of hearing efficiently.

Auditory Ossicles

Auditory ossicles are tiny bones found within the middle ear. There are three of them, known as the malleus, incus, and stapes. These bones are unique to mammals and are vital for transmitting sound from the outer ear to the inner ear.

• The malleus, connected to the eardrum, receives sound vibrations first.
• These vibrations are then passed on to the incus, which acts as a lever.
• Finally, the stapes sends these vibrations to the oval window of the cochlea in the inner ear.

The cochlea converts these vibrations into electrical signals that the brain interprets as sound. Without auditory ossicles, our ability to hear would be significantly impaired. These bones enhance the sound, making sure the sound levels are sufficient for the cochlea to process.

Middle Ear

The middle ear is a small, air-filled cavity located behind the eardrum. It functions as an efficient conductor of sound from the external environment to the inner ear. Inside the middle ear are the three auditory ossicles: malleus, incus, and stapes. Together, they form a bridge connecting the eardrum to the inner ear.

• The middle ear starts at the eardrum and ends at the oval window, leading to the inner ear.
• It also contains the Eustachian tube, which helps equalize air pressure between the middle ear and the atmosphere.
• This pressure regulation is crucial for proper hearing and is why we often experience ear discomfort during rapid altitude changes, like in flights.

Understanding the structure and function of the middle ear is essential for comprehending the mechanics of hearing and how sound waves efficiently reach the auditory nerves.