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

Question, Ask questiImagine you are studying a group of amphibian species t...

Ask questiImagine you are studying a group of amphibian species that vary in their habitats-some living in dense, murky water, and others living in very clear ponds. What kind of c

Internal structure of mammalian heart, INTERNA L STRUCTURE - Wall o...

INTERNA L STRUCTURE - Wall of auricles are thin than wall of ventricles, because they have to push the blood to ventricles only situated close to them. Walls of ventricl

Toxoplasmosis, Toxoplasmosis Toxoplasmosis, one of the important parasitic...

Toxoplasmosis Toxoplasmosis, one of the important parasitic zoonoses, occurs all over the world, and is caused by a protozoan parasite Toxoplasma gondii. Its definitive hosts are

Find if the sugar is a d- or l- stereoisomer, If carbon 1 is the carbonyl g...

If carbon 1 is the carbonyl group of a 6-carbon aldose (aldohexose), which carbon determines if the sugar is a D- or L- stereoisomer? Select one: a. 1 b. 2 c. 3 d. 4

Discovery of plant hormones, Discovery of Plant Hormones To date, five...

Discovery of Plant Hormones To date, five major classes of plant hormones have been discovered namely auxins, gibberellins, cytokinins, abscisic acid and ethylene. It is possi

Define the term - microfilaments and microtubules, Define the term - microf...

Define the term - microfilaments and microtubules The cytoskeleton is, in fact, termed as the "bone and muscle" of the eukaryotic cell, and is composed of a network, consisting

Cartilage occur in a joint and what it its function, Where does cartilage o...

Where does cartilage occur in a joint and what it its function? Cartilage might be found covering the surface of bones where they meet in a movable joint. Cartilage decreases f

Regular soda are made with aluminium, If the cans of regular soda are made ...

If the cans of regular soda are made with aluminium than diet soda, then regular soda will sink. Write brief descriptions of how you could test this hypothesis.

Classification of multicellular animals - coelom, Classification of Multice...

Classification of Multicellular Animals - Coelom We know earlier that the pseudocoel gave animals specific selective benefits. Among other things, this fluid-tilled space wor

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