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

How phytohormones help development of parthenocarpic fruits, How phytohormo...

How phytohormones help the development of parthenocarpic fruits? The Parthenocarpic fruits are those produced with no fecundation. Several plants naturally make parthenocarpic

Explain about the epilepsy, Explain about the Epilepsy? Epilepsy is a n...

Explain about the Epilepsy? Epilepsy is a neuromuscular disorder in which transient seizures recur due to an abnormal brain activity. The brain, through all orderly electric ex

Zoonoses disease-leptospirosis, Leptospirosis Leptospirosis is a gener...

Leptospirosis Leptospirosis is a general term that denotes all infections of man and animals caused by spirochaetes of the genus Leptospira. At one time, the infection had bee

Palaeontological evidence of evolution, EVIDENCES OF EVOLUTION - The ev...

EVIDENCES OF EVOLUTION - The evidences of organic evolution derived from many lines of study indicate that present day forms have arisen by gradual changes from pre existing fo

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

What is an argument that shows emergence of photosynthetic, What is an argu...

What is an argument that shows that the emergence of photosynthetic beings was crucial for life to reach the marine surface and later the dry land? The Ultraviolet radiation fr

Define compartments of extracellular fluid, Define Compartments of Extracel...

Define Compartments of Extracellular Fluid? The extracellular fluid compartment is further subdivided into several smaller compartments. These include: 1. Plasma 2. The i

Planning of nursing care - acute glomerulonephritis, Planning of Nursing Ca...

Planning of Nursing Care   Provide supportive and symptomatic treatment.  Provide bed rest.  Encourage diet restriction,  Implementation  of Nursing Care

Define dietary management of cancer patients, Define Dietary Management of ...

Define Dietary Management of Cancer Patients and Feeding Problems Related To Cancer Therapy? We took an overview about the general nutritional requirements of cancer patients.

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