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

Chapter-2, multiple choise question

multiple choise question

Determine the uses of potassium, Determine the uses of Potassium Water ...

Determine the uses of Potassium Water soluble and exchangeable potassium is readily available to plants. This is extracted with Morgan reagent (10% sodium acetate in 3% acetic

Explain environmental resistance and the population growth, What is the rel...

What is the relationship among environmental resistance and the population growth according to the biotic potential curve and the real population growth curve? The difference

Phylum , General characteristics of phylum

General characteristics of phylum

What is the spontaneous generation hypothesis, What is the spontaneous gene...

What is the spontaneous generation hypothesis? The impulsive generation abiogenesis or hypothesys asserts that life on earth has come from nonliving material. For instance, t

Enzyme-activity control, Enzyme-activity Control Availability of the s...

Enzyme-activity Control Availability of the substrate, NADH and nitrate would be an important determinant of the rate of nitrate assimilation. In addition, there are number of

Explain the nutritional and functional role of sulphur, Minerals :-  Sulfur...

Minerals :-  Sulfur Food Source       Widely distributed  Nutritional Functional role Essential nutrient: A constituent of the essential amino acids methionine and

Curve of variation of the speed of a reaction, Q. Concerning enzymatic reac...

Q. Concerning enzymatic reactions, how dissimilar are the graphic curve of the variation of the speed of a reaction as function of substrate concentration and the curve of variatio

What is the binding between two amino acids, Q. What is the binding between...

Q. What is the binding between two amino acids called? The chemical bond between two amino acids is called a peptide bond.

Phylum, general charactristics of phylum protozoa

general charactristics of phylum protozoa

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