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

Explain the factors affecting the process of deep fat frying, Factors affec...

Factors affecting the process of deep fat frying. The common factors influencing the process of deep frying include: 1.  Heat- Frying temperatures ranging from 150 -190°C

Cell membrane, CELL MEMBRANE As discrete units of life  all living cell...

CELL MEMBRANE As discrete units of life  all living cells are separated from each other and from their external environment by an  extremely delicate (75 A to 100 a= 0.00075 to

Biological functions in which chlorine ions participate, Q. What are the ma...

Q. What are the major biological functions in which chlorine ions participate? Like sodium cations, chlorine anions actively participate in the regulation of the osmolarity of

Water adaptations, Water Adaptations After becoming familiar with the t...

Water Adaptations After becoming familiar with the two kinds of water stresses you would like to know about the adaptations in plants and animals which enable them to survive u

Agro industrial-enrichment of soil, Enrichment of soil Indirect provis...

Enrichment of soil Indirect provision of minerals to grazing livestock includes mineral fertilization of  pasture and altering soil pH, however this may not be always feasible

What is a monohybrid cross, A monohybrid cross: A.Determines the genetic ma...

A monohybrid cross: A.Determines the genetic makeup of an organism B.always involves homozygous alleles. C.always involves organisms that are heterozygous at all loci. D.Always inv

Deficiency diseases-osteomalacia, Osteomalacia Similar to rickets in yo...

Osteomalacia Similar to rickets in young growing animals, osteomalacia is a disease of mature animals caused by absolute or relative deficiency of any one or combination of cal

Determine the steps for withdrawing the insulin, Determine the Steps for Wi...

Determine the Steps for Withdrawing the Insulin The important thing about measuring a dose is to use the front of the plunger not the back - Check doctor's prescription.

Carbohydrates, Carbohydrate - contains Carbon , Hydrogen , and Oxygen ...

Carbohydrate - contains Carbon , Hydrogen , and Oxygen with a general formula of C x (H 2 O) y Simple sugars à monosaccharides Oligosaccharide à sugars containing

What are the major purposes of the organic molecules, Q. What are the major...

Q. What are the major purposes of the organic molecules for living beings? Ans. Organic molecules, like, lipids, carbohydrates and proteins perform several functions for

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