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

What is class amphibia , What is Class Amphibia ? Class Amphibia take...

What is Class Amphibia ? Class Amphibia takes its name from the Greek words "amphi" and "bios." Amphi means "both sides," or "both types," and bios means "life." This name-bo

Experiment of a study of broken rock, A study of broken rock Break open...

A study of broken rock Break open several rock specimens. Compare the appearance of freshly broken surfaces with the Heather-worn outside of the rock. The rocks may be safely b

Prolactin - vertebrates, Normal 0 false false false EN-...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Protein synthesis, Where in eukaryotic cells does mRNA synthesis occur? To ...

Where in eukaryotic cells does mRNA synthesis occur? To where do these molecules migrate?

Sources of food contamination, All plants and animals have a natural microf...

All plants and animals have a natural microflora associated with them. For example, the plants have a natural microflora associated with the surface of roots, stems, leaves e

Explain binding of pigments - proteins, Binding of  Pigments, synthetic dy...

Binding of  Pigments, synthetic dye In  addition  to water, lipids and  volatile  flavours,  food proteins  can  bind  a number of other  substances  by  weak interactions  or

Polygonum type - monosporic embryo sacs, Polygonum Type - Monosporic Embryo...

Polygonum Type - Monosporic Embryo Sacs The embryo sac is formed from the chalazal megaspore in the tetrad and is eight-nucleate. The development of the embryo sac begins with

Define limitations for standard or total plate counts method, Define Limita...

Define Limitations for Standard or Total Plate Counts Method? This method has certain limitations - 1. Microbial count depends on the type of media, incubation temperature,

Technique of operation, Technique of Operation :  TEE probe i...

Technique of Operation :  TEE probe is passed in all cases soon after anaesthesia. The initial steps and exposure of mitral valve are done as for open mitral valvotom

How can you describe the homeostasis, Q. What is the homeostasis? What are ...

Q. What is the homeostasis? What are the sensors, effectors and controllers of homeostasis? Homeostasis comprises the processes by which the organism maintains extracellular an

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