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

Denaturing gel, Denaturing Gel is an agarose or the acrylamide gel run und...

Denaturing Gel is an agarose or the acrylamide gel run under conditions which destroy the secondary or tertiary protein or RNA. For protein, this generally means the inclusion of

What are the reasons of food processing, What are the reasons of Food Proce...

What are the reasons of Food Processing? The reasons for food processing may vary, but the main objectives are to: Preserve the nutritive quality of food by preventing th

Lymph, LYMPH - Lymph is a mobile connective tissue comprising lymph pla...

LYMPH - Lymph is a mobile connective tissue comprising lymph plasma (fluid) and lymphcorpuscles (cells).   COMPOSITIO N - (i )      Lymph Plasma - It is simil

Mitosis, What are the steps of mitosis in order?

What are the steps of mitosis in order?

Filariasis, Filariasis Filariasis is a chronic infection caused by filarid...

Filariasis Filariasis is a chronic infection caused by filarid worms. Around 10 species of Filaridae family are parasitic to man. Adult worms live in the tissues or body cavities

Names and uses of the various laboratory tools, What are the names and uses...

What are the names and uses of the various laboratory tools? Tools are beakers, microscopes, tweezers, hot plates, lasers, test tubes, voltmeters, Erlenmeyer flasks, thermomete

Define genetic susceptibility factors for obesity, Define Genetic Susceptib...

Define Genetic Susceptibility Factors for Obesity? Some people inherit a tendency to become fat. Earlier, it was thought that genetic inheritance ranged from 66% to 80% but now

Phylum mollusca, what is salen and its characterstics

what is salen and its characterstics

Locomotion, discuss locomotion in annelids

discuss locomotion in annelids

What are the autotrophic beings called, In the ecological study of food int...

In the ecological study of food interactions, what are the autotrophic beings called? In the Ecology autotrophic beings are called as producers because they synthesize the orga

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