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

The excretion by the human kidney, The excretion by the human kidneys 1...

The excretion by the human kidneys 1. Descending limb of Loop of Henle is impermeable to water 2. Distal convoluted tubule is incapable of reabsorbing HCO3 3. Nearly 99 p

Protein necessity, Proteins necessity They are called as body builde...

Proteins necessity They are called as body builders. The proteins are used in various metabolic pathways and body building. They help in repairing the tissues of the b

Define phospholipids, a) Lipoproteins are large molecular compounds that a...

a) Lipoproteins are large molecular compounds that are essential to the transport of cholesterol and triglycerides (TGs) within the blood. They contain a lipid core composed of TG

What is phosphorylation, Q. What is phosphorylation? What are various biolo...

Q. What is phosphorylation? What are various biological processes in which phosphorylation plays a critical role? Phosphorylation is the name given to procedure of the addition

Find the magnitude and the direction of his initial velocity, After leaving...

After leaving the end of a ski ramp, a ski jumper lands downhill at a point that is displaced 66.2 m horizontally from the end of the ramp. His velocity, just before landing, is 18

Lower oesophageal sphincter, Q Lower Oesophageal Sphincter? Competency ...

Q Lower Oesophageal Sphincter? Competency of LES (Lower Oesophageal Sphincter) is important. The pressure of this sphincter is controlled by many factors, one of which is hormo

What is plaque, What is plaque? Plaque is a film over the teeth and hav...

What is plaque? Plaque is a film over the teeth and having of saliva, mucus, bacteria and the substances they produce. It may also have mineral salts of calcium and magnesium.

Haematology, differenciate between plasma and serum

differenciate between plasma and serum

Indications for gingival curettage - endodontic surgery, Indications for Gi...

Indications for Gingival Curettage - Endodontic Surgery a) Persistent periradicular pathosis following endodontic treatment, b) Periradicular lesion that enlarges after endo

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