Can you explain myopia and hypermetropia, Biology

Assignment Help:

Q. How can the visual deficiencies known as myopia and hypermetropia be optically explained?

Myopia is the visual condition in which the images are formed previous to (in front of) the retina. Hypermetropia is the visual condition in which the point of image formation is further than (behind) the retina. Actually myopia is due to an increase in the distance between the crystalline lens and the retina, generally caused by a slight flattening of the eyeball and in hypermetropia the retina is too close to the crystalline lens due to slight shortening of the eyeball.

In myopia the far point and the near point of vision come closer (the refractivity of the crystalline lens that corresponds to the maximum distension capacity of the ciliary muscles isn't enough to provide visual accommodation). In hypermetropia the ciliary muscles aren't able to contract more to compensate the inadequate position of the retina that is the near point becomes more distant.


Related Discussions:- Can you explain myopia and hypermetropia

What are the advantages of the closed circulatory system, What are the adva...

What are the advantages of the closed circulatory system over the open circulatory system? The closed circulatory system is more efficient. As blood circulates only inside bloo

Feeding mechanism in holozoic organism, write short note on feeding mechani...

write short note on feeding mechanism in holozoic organism

What are the sources of nutrients of cornea, What are the Sources of Nutrie...

What are the Sources of Nutrients of Cornea? Sources of Nutrients of Cornea: 1) Oxygen for the endothelium comes from aqueous humour and for epithelium from atmosphere th

Cooking loss and quality of products, Coo k in g loss and quality Yi...

Coo k in g loss and quality Yields and cooking losses of products are important as these determine acceptability and economics of products. Higher cooking losses increase th

Show the ph range of natural honey, Q. Show the pH range of natural honey? ...

Q. Show the pH range of natural honey? The pH of natural honey ranges from 3.4 to 6.1. Acidity of honey is primarily due to presence of acids such as gluconic acid, pyruvic a

What is the structure of the adult fern, What is the structure of the adult...

What is the structure of the adult fern within which cells undergoing meiosis can be found? In these plants meiosis takes place within structures known as sorus (plural, sori),

Leptospirosis, L e p t o s p i r o s i s It is zoonotic dis...

L e p t o s p i r o s i s It is zoonotic disease characterized by interstitial nephritis, haemolytic anaemia and abortions. E t iology : The disease i

Consequences of shifting the chemical equilibrium, Q. What are the conseque...

Q. What are the consequences of shifting the chemical equilibrium of the formation of bicarbonate from carbon dioxide and water towards the increase of product (bicarbonate) format

Examine the blood types, Discuss blood types, the factors in crime scenes. ...

Discuss blood types, the factors in crime scenes. What is a criminal case where blood samples were important in the case decision and outcome, what was it about the blood in this c

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