Anatomy and Physiology tutorial

Outer ear consists of

• Pinna / auricle

• Tympanic membrane

• External auditory meatus

• Utricle

What are the functions of Pinna?

• Collects sound wave and directs to external auditory canal

• Protects ear canal

• Serve as a resonator

• helps to localize sound

What are the incorrect facts about external auditory meatus (EAM)

• 23–29 mm in length

• A narrow “C” shaped canal

• Skin in the cartilaginous portion of the canal contains glands

• Inner two thirds is composed of skin-covered cartilage

what is/ are the correct statement/s?

• Malleus has a foot plate

• Tympanic membrane is a concave shaped membrane

• Eustachian tube connects middle ear with oropharynx

• Tympanic membrane is made of several layers of cartilage

what is the correct order of ear ossicles ?

• Incus, Malleus, Stapes

• Malleus, Stapes, Incus,

• Malleus, Incus, Stapes

• Stapes, Malleus, Incus

Eustachian tube,

• Equalizes pressure between the outer ear and middle ear

• dysfunction can cause ringing in the ear

• Most of the time the eustachian tube is closed

• Also called as laryngotympanic tube

Cochlea

• an air filled space

• Has 3 channels

• contains sensory parts of both hearing and balance.

• has 2.5 turns

what are the correct statements

• ´Scala media is filled with perilymph.

• Scala media lies between the scala vestibuli and scala tympani.

• Reissner’s membrane separates Scala media from scala tympani

• Scala media is filled with endolymph.

Organ of Corti

• haircells are elongated in shape

• Rests on the basilar membrane

• Outer hair cells present only in the helicotrema

• There are three rows of outer hair cells

what is/are the wrong statement/s?

• Utricle and saccule respond to angular acceleration

• sensory receptor organs of the utricle and saccule are called the maculae

• Semicircular canals are at right angles to each other.

• On top of otolith membrane, calcium carbonate crystals called otoliths are situated