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

Enzyme-controlled reaction, If an enzyme-controlled reaction normally takes...

If an enzyme-controlled reaction normally takes place at 10ºC, in general terms how will the reaction be affected by  (a) a fall in temperature to 2°C , (b) a rise in temperature t

Respiration, difference between the respiration occurs in lower and higher ...

difference between the respiration occurs in lower and higher organisms

Volvocine Protozoa, Why is Volvocine Protozoa not considered an animal?

Why is Volvocine Protozoa not considered an animal?

What is intermittent treatment, Intermittent Treatment Intermittent 4...

Intermittent Treatment Intermittent 4-drug regimens with 2 or 3 doses per week after at least 2 weeks of daily therapy are also effective for treatment of TB and should alway

What are the constituent elements of the blood, Q What are the constituent ...

Q What are the constituent elements of the blood? The blood is made of a liquid and a cellular part the fluid part is called as plasma and in it there are several substances li

Explain about modifiable risk factors, Q. Explain about Modifiable Risk Fac...

Q. Explain about Modifiable Risk Factors? 1. Behavioural Smoking Sedentary Lifestyle Habits Dietary Errors 2. Physiological Hyperlipidemia Hypertension Obe

What are the reagents and products of fermentation, In general what are the...

In general what are the reagents and products of fermentation? In fermentation glucose (sugar) is degraded into pyruvic acid (every glucose molecule forms two pyruvic acid mole

Spermatogonia - spermatozoa, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4 Spermatogonia - Spe

FISHERIES, skeletal system of fish .exoskeleton and endoskeleton

skeletal system of fish .exoskeleton and endoskeleton

Cow-pox (vaccinia), Epidemiology: This infection, although mostly occurrin...

Epidemiology: This infection, although mostly occurring in cows, sometimes also occurs in buffaloes. Under natural conditions, the infection takes place through inoculation by 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