Middle ear, Biology

Assignment Help:

MIDDLE EAR -

  1. Protected by tympanic bone. It's cavity is tympanic cavity.
  2. It is lined by simple cilliated columnar epithelium. It is connected to naso pharynx by Eustachian canal.
  3. Here valve is present, generally closed, during shouting, yawning & swallowing it is opened.
  4. Due to it on both sides of tympanum, pressure of air is equalized. Inflamation of eustachian tube is eutachitis.
  5. Cold may block the eustachian tube & the pressure outside and inside the middle ear do not equalige. So divers and fliers do not work when they have cold. Outside preesure is increases in diving & decresed in flying.
  6. Middle ear is connected to internal ear by fenestra ovalis or oval window and fenestra rotundus or round window.
  7. By fenestra ovalis sound waves enter in to internal ear. By fenestra rotundus sound waves come out if strong.
  8. Between tympanum and fenestra ovalis there is a chain of 3 bones collectively called as ear ossicles.
  9. Three bones are malleus, inchus & stapes. Malleus is hammer shaped attached to tympanum.
  10. Inchus is anvil shaped. Stapes is stirrup shaped, smallest bone with bone marrow.
  11. All bone are articuluted by hinge joint & fixed in position due to their respective ligaments.
  12. These bones are modification of articular, quadrate and hyomendibular.
  13. In frog collumella auris present, which is modification of hyomendibular.
  14. Ear ossicles transmit the vibration from the tympanic membrane to internal ear and also amplify them about 20 times.
  15. Two small muscles tensor tympani and stapedius, joined to malleus and stapes respectively, contract to prevent damage to the dellicate internal ear at the time of loud sound.

Related Discussions:- Middle ear

Calculate the probability that both are carriers for tsd, The male had a fe...

The male had a female first cousin (on his father side) who died from TSD and the female had a maternal uncle with TSD. Assume this trait is very rare. 1. Calculate the probabil

Muscular tissue, MUSCULA R TISSUE Muscular tissue in general develop...

MUSCULA R TISSUE Muscular tissue in general develops from the mesoderm of the embryo but the muscles of the iris of the eye and myoepithelial cells of the salivary, mammar

Why is pattern baldness more common in men than in women, Why is pattern ba...

Why is pattern baldness more common in men than in women? Pattern baldness is handled by the allele B. Testosterone interacts with the heterozygous genotype (BB′) to make baldn

What is genesis of coronary artery diseases, What is genesis of coronary ar...

What is genesis of coronary artery diseases ? Like any other disease conditions, origin of CAD depends on an interplay between the heredity and environment so called 'nature' a

Plant might be adapted to a hot dry environment, Give three ways in which a...

Give three ways in which a plant might be adapted to a hot dry environment. A plant might be adapted to a hot dry environment by having a decreased leaf area, waxy cuticle to

Ruminal tympany (bloat), R uminal tympany (Bloat) It is the over-diste...

R uminal tympany (Bloat) It is the over-distension of the rumen with gases which may be either frothy or free gas. The disease is characterized by change in silhouette of the

Entomophily - cross-pollination, Entomophily - Cross-pollination It in...

Entomophily - Cross-pollination It involves insects to carry the pollen to achieve pollination. Salvia exhibits a specialised 'tumapipe' floral mechanism that signifies classi

Explain isomer, Isomer : Existence of different  compounds having  same ...

Isomer : Existence of different  compounds having  same  molecular form but different structural forms.

Explain about dietary management, Q. Explain about Dietary Management? ...

Q. Explain about Dietary Management? Treatment for gout often include a diet of lower purine intake. Indeed, about one third of the body's uric acid can be attributed to diet.

Define proteins, Define Proteins, Carbohydrates required for anorexia nervo...

Define Proteins, Carbohydrates required for anorexia nervosa? A. Proteins To ensure adequacy, minimum protein intake should equal the recommended dietary intake for age and

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd