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

Biotechmology, how to write a assignment on autoradiography

how to write a assignment on autoradiography

Simple tips to diarrhoea patient, A few simple tips which should be given t...

A few simple tips which should be given to the patient. • Boiling, steaming, baking, pressure cooking should be encouraged • Consume small and light meals frequently instea

List the four phases of mitosis, List the four phases of mitosis, and brief...

List the four phases of mitosis, and briefly explain what occurs during each phase. Prophase: the chromatin coils and produces chromosomes, the nucleolus and nuclear envelope d

Define the term - cerebral arteriosclerosis, Define the term - cerebral art...

Define the term - cerebral arteriosclerosis An embolism can be a blood clot, a bubble of air, a deposit of oil or fat, or a small mass of cells detached from a tumor. Reduction

Foot-and-mouth disease - viral disease, F o o t - a n d - m o u ...

F o o t - a n d - m o u t h disease Foot-and-mouth disease (FMD) is an extremely contagious viral disease of cloven footed animals most notably cattle, pig and she

Define transport and uptake of zinc by cells, Define Transport and uptake o...

Define Transport and uptake of Zinc by Cells? After absorption, zinc is bound to albumin and transported to the liver. In liver, it is concentrated and then transported to diff

Determine the ecosystem if the decomposers were eliminated, What would happ...

What would happen to the energy flow through an ecosystem if the decomposers were eliminated?  Without decomposers, the nutrients kept in the bodies and wastes of other organis

Acute versus chronic heart failure, When the syndrome sets in at a rapid ra...

When the syndrome sets in at a rapid rate before the compensatory mechanisms become operative, acute heart failure develops. The examples are acute heart failure due to acute myoca

Explain some food applications of pectin, Explain Some food applications of...

Explain Some food applications of pectin As with other viscous polyanions such as carrageenan, pectin may be protective towards milk casein colloids, enhancing the properties (

How many distinct hexapeptides made from 20 amino acids, How many distinct ...

How many distinct hexapeptides can be made from 20 amino acids?

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