Anatomy - Ear Flashcards
What are some functions of the ear?
Balance, audiology
What are the basic anatomical features of the ear?
External ear (pinna and canal), middle ear and mastoid system, inner ear
What are the features of the external ear?
Pinna - skin = stratified keratinising squamous epithelium, elastic cartilage structure
EAM - lateral 1/3 cartilage and skin, medial 2/3 bone and skin, features ceruminous and sebaceous glands - was production
Describe the tympanic membrane
Approximately 1cm diameter, 3 layers
What are the 3 layers of the tympanic membrane?
- outer squamous epithelium
- middle fibrous connective tissue
- inner columnar ciliated mucous membrane
What is the ossicular chain?
Three small bones in the middle ear; the malleus, incus and the stapes. It plays a key role in sound conduction
How can the ossicular chain be damaged?
Trauma, chronic suppuration, bony sclerosis (osteosclerosis)
What is the epithelium of the middle ear?
Columnar ciliated epithelium
What are the basic components of the middle ear?
Ossicles, facial nerve, chorda tympani
What are the dangers of infection and trauma to the ear?
Intracranial sepsis, facial nerve damage, deafness, dizziness
What is the vestibule?
The cochlear organ, a component of the inner ear which plays a key role in balance and hearing
What is the bony labyrinth?
The cochlea, vestibule, semi-circular canal
What is the membranous labyrinth?
Sensory epithelium of the inner ear
What fluids are in the inner ear?
Perilymph and endolymph
