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

Define some precautions for measurement of ph, Define some Precautions for ...

Define some Precautions for Measurement of pH? 1. Never touch the membrane of the glass electrode with anything else except soft tissue paper since it is fragile and is easily

What is the average number of minutes a cell, You have 200 cells and find 1...

You have 200 cells and find 120 in interphase, 57 in prophase, 8 in prometaphase, and 5 in metaphase, 8 in anaphase and 2 in telophase. (None in G0 phase). it takes 18 hours to com

Dissolved oxygen - aquatic habitats, Dissolved oxygen - Aquatic Habitats ...

Dissolved oxygen - Aquatic Habitats Oxygen in the terrestrial ecosystems occurs in the atmosphere along with other gases in a certain fixed concentration however, in aquatic e

Planning and implementation of nursing care-aplastic anaemia, Planning of N...

Planning of Nursing Care     Administer the drugs as prescribed -    Prevent infection    Control bleeding  Implementation of Nursing Care   Administer th

Coeleterates, what are the characteristics of cleavage formed in coelentera...

what are the characteristics of cleavage formed in coelenterates?

Care required by a hiv infected person, Care required by a HIV infected per...

Care required by a HIV infected person: 1) An HIV infected person needs acceptance and support from the family members. The home is very important place for a person with AIDS.

Causes of diabetic ketoacidosis, Q. Causes of Diabetic Ketoacidosis? Th...

Q. Causes of Diabetic Ketoacidosis? The causes of Diabetic Ketoacidosis (DKA) are the following: - Missing of insulin injection - Infection - Trauma (injury) - Myoc

Determine the categories of sleep disorders, Determine the categories of sl...

Determine the categories of sleep disorders Sleep disorders are generally divided into two major groups: 1) Narcolepsy, which is characterised by excessive sleep or brief in

Plant physiology, why does the removal of extremity of coleoptile prohibit ...

why does the removal of extremity of coleoptile prohibit plant growth?

What is the primary structure of a protein, What is the primary structure o...

What is the primary structure of a protein? What is the significance of the primary structure? The primary protein structure is the linear sequence of amino acids that form the

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