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

Show the parameters which are of interest in chd, Q. Show the parameters wh...

Q. Show the parameters which are of interest in CHD? Total Cholesterol: Serum totnl cholesterol equals the sum of HDL-cholesterol (HDL-c), VLDL-cholesterol (VLDL-c) and LDL-cho

Name main parts into which a neuron can be divided, What are the three main...

What are the three main parts into which a neuron can be divided? What are their respective functions? The three mains parts into which a neuron can be didactically separated a

Explain briefly about vitamin B12, Vitamin B 12 (Cyanocobalamin) Vitam...

Vitamin B 12 (Cyanocobalamin) Vitamin B 12 refers to a group of Cobalt-containing corrinoids known as cobalamins. It is also called antipernicious- anemia factor, extrinsic f

Nervous system - brain, BRAI N (ENCEPHELON) Shape - Oval Positio...

BRAI N (ENCEPHELON) Shape - Oval Positio n - Situated in cranial cavity of skull. Medulla oblongeta comes out of foramen magnum in the form of spinal cord. Colou

Determine the muscarinic acetylcholine receptors, Which of the following se...

Which of the following serves as an effector, or as part of an effector, that functions in a negative feedback system? A. Muscarinic Acetylcholine Receptors (mAChRs) in the SA

What is haccp, What  is  HACCP? HACCP, as you may  already know,  is ...

What  is  HACCP? HACCP, as you may  already know,  is an acronym that stands for Hazard Analysis Critical  Control Point,  a systematic, science-based approach  used  in  food

What is mitochondrial inheritance?, What is mitochondrial inheritance? ...

What is mitochondrial inheritance? The Mitochondrial inheritance is the passage of mitochondrial DNA molecules (mtDNA) to the offspring. All the stock of mtDNA an individual ha

Aeration, Aeration A well-aerated soil is one in which gases are availa...

Aeration A well-aerated soil is one in which gases are available to plant roots and other soil organisms, in sufficient quantities and in proper proportions to support their no

Define the drugs effects on excretion, Define the Drugs Effects on Excretio...

Define the Drugs Effects on Excretion? Use of certain drugs can influence the excretion of certain substances. For example, besides their intended increase in sodium excretion,

Gene clonning, Inportant step for gene clonning

Inportant step for gene clonning

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