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 is single cross between two mountain rabbits, In mountain rabbits, the...

In mountain rabbits, the EL-1 gene is located on chromosome 3. Seven alleles of this gene have been identified in the population. With respect to EL-1, what is the maximum number o

Parasitic adoptaion in animal, #question.what do u mean by parasitic habit....

#question.what do u mean by parasitic habit.give account of various parasitic adoptation in animal.

Functions of cerebrum, Functions of cerebrum The forebrain is otherw...

Functions of cerebrum The forebrain is otherwise called as ‘cerebrum'. It is highest centre for controlling several functions in the body, The most interesting aspect

What are the three qualities specific to colour vision, What are the three ...

What are the three qualities specific to colour vision There are three qualities specific to colour vision- hue, saturation, and brightness. Hue: Hue is the function of a wa

Nerves found in human body, Motor nerves : Nerves which carry impulses fro...

Motor nerves : Nerves which carry impulses from brain or spinal cord to effector organs are called efferent or motor nerves. Stimulation of motor nerves makes the muscles to contr

Primary prevention of diabetes mellitus, Q. Primary prevention of diabetes ...

Q. Primary prevention of diabetes mellitus? Approaches to Prevention: There are various approaches to prevention. Four levels of prevention related to different stages of a di

Storage and distribution - sterilization process, Packs, pouches, and casse...

Packs, pouches, and cassettes are sometimes wet after completing the sterilization process. This is a problem usually associated with the use of paper or paper/ plastic wraps in t

Explain nutritional support management - cancer patient, Explain about the ...

Explain about the Nutritional Support Management? Tube feeding is usually started. If tube feeding is not possible, parenteral nutrition through peripheral vein or through the

Eliminate heat energy at the rate of approximately, A large leaf on a plant...

A large leaf on a plant in bright sunshine evaporates 5 grams of water per hour. Cooling the leaf through evaporation in this manner enables the plant to eliminate heat energy at t

State about electric field lines, State about Electric Field Lines Ele...

State about Electric Field Lines Electric Field Lines (lines of force) - show direction of force on a positive test charge from a distribution of charges.  The electric field

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