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 constitutional unit of proteins, Q. What is constitutional unit of ...

Q. What is constitutional unit of proteins? The constitutional units of proteins are the amino acids.

Which elements contains carbohydrates, (a) Which elements contains Carbohyd...

(a) Which elements contains Carbohydrates (b) Which elements contains Proteins   a) Carbohydrates contain the elements carbon , hydrogen and oxygen. b) Protei

Explain about the fermentation - methods of food processing, Explain about ...

Explain about the Fermentation - methods of food processing? In contrast to other preservation methods, multiplication of microorganisms and their metabolic activities are enco

Parthenogenesis, what are the consequences of parthenogenesis in human life...

what are the consequences of parthenogenesis in human life if humans reproduced through parthenogenesis?

Explain glycophorin, Since erythrocytes  red blood cells do not hold any su...

Since erythrocytes  red blood cells do not hold any sub cellular  organelles they are essentially  a membranous  sac for carrying  haemoglobin their plasma membrane  is a convenien

Blood from the fetus circulates through the placenta, Blood from the fetus ...

Blood from the fetus circulates through the placenta. a) What substances pass (i) from the maternal to the fetal blood, (ii) from the fetal to the maternal blood?

Mucoproteins (glycoproteins), MUCOPROTEIN S (GLYCOPROTEINS) Protein...

MUCOPROTEIN S (GLYCOPROTEINS) Proteins having conjugated mucosaccharides that form viscous mucus or mucoid secretions. The gastric mucus or mucoprotein is resistant to p

Promotion - stages of carcinogenesis, Promotion - Stages of carcinogenesis ...

Promotion - Stages of carcinogenesis The second stage or promotion is reversible and does not include changes in structure of DNA but rather in the expression of the genome of

Silviculture, Silviculture: It concerned with the cultivation of timber yi...

Silviculture: It concerned with the cultivation of timber yielding plants. Silviculture is the way of controlling the growth, establishment, composition, health or quality of fore

Indifferences in ionic composition, Indifferences in ionic composition Answ...

Indifferences in ionic composition Answer A. across membranes can be created through the action of ATP driven pumps as long as number of negative and positive ions on remain equal

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