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

Mosaic endosperm - variants of endosperm, Mosaic Endosperm - Variants of En...

Mosaic Endosperm - Variants of Endosperm In some plants patches of two different colors appear in the tissues of the endosperm providing a mosaic design. In maize, red and whi

Explain about g-protein, Explain about G-protein   A.  When an agonist ...

Explain about G-protein   A.  When an agonist binds to the binding site of a G-protein-coupled receptor (GPCR), this leads to GTP displacing a GDP bound to the alpha subunit of

Express how that system accomplishes that necessity, Name a system that acc...

Name a system that accomplishes that necessity and explain how that system accomplishes that necessity.

Intraspecific and interspecific competition, In the preceding block you lea...

In the preceding block you learnt the Darwinian premise of natural selection based on certain facts and deductions thereof. You would have noticed that one of the foundations for t

Describe the working of ploidy reduction, Q. During which meiosis division ...

Q. During which meiosis division does ploidy reduction take place? And Does it ploidy reduction occur in mitosis? In the cell division by meiosis ploidy reduction occurs in mei

Mitral valve replacement -mitral valve disease, Mitral Valve Replacement : ...

Mitral Valve Replacement :  Patients who require surgery and are not candidates for BMV, CMV or OMV should have mitral valve replacement (MVR). Types of Surgery for Mitra

Electronic chip is implanted in the body – vivo and vivo, An electronic chi...

An electronic chip is to be implanted in the body. During in vitro (in the lab) testing it is observed that the chip will dissolve over time if exposed to liquid with similar pH to

From which germ layer epidermis and nervous system originate, Q. From which...

Q. From which germ layer do the epidermis and the nervous system originate? What are other organs and tissues made from that germ layer? Epidermis and nervous system have the s

Describe two differences among green algae and red algae, Some biologists p...

Some biologists prefer to categorize brown, red, and some green algae as plants rather than protists. What characteristics of these algae support like classification? Brown and

Explain properties of colloidal systems - electric charge, Electric Charge ...

Electric Charge - Properties of Colloidal Systems Colloidal particles are electrically charged. Some colloidal particles carry a positive charge (+), others a negative charge (

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