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

Define altered glucose metabolism - nutrition during stress, Define Altered...

Define Altered Glucose Metabolism - Nutrition during Stress? Blood glucose levels are generally elevated in the infected patient but plasma insulin levels are normal or even hi

Describe cytokinesis in a plant cell, Describe cytokinesis in a plant cell....

Describe cytokinesis in a plant cell. Vesicles produced by the Golgi apparatus fuse at  the midline of the cell to form the cell plate, a  cell wall that elongates to divide th

How to load glycogen, How to load glycogen? Over the past fifty years, ...

How to load glycogen? Over the past fifty years, the biggest breakthrough was the discovery of how to load glycogen and sophistication in the methods of glycogen loading. Nitro

Infructescences- pseudofruits and parthenocarpic fruits, What are the infru...

What are the infructescences, pseudofruits and parthenocarpic fruits? The Infructescences are aggregated fruits formed from inflorescences, aggregated flowers. Grape clusters a

Neurosecretory cells and neurosecretion, Neurosecretory Cells and Neurosecr...

Neurosecretory Cells and Neurosecretion We have before said that the neurosecretory cells are an important component of the non- chordate endocrine system. Of course, they are

Toxoplasma cycles, Toxoplasma cycles between its rodent and feline hosts,li...

Toxoplasma cycles between its rodent and feline hosts,living out different phases of its existence in each. what is the scientific means about the cat and mouse.

Determine the role as antioxidant, Determine the Role as antioxidant? S...

Determine the Role as antioxidant? Some carotenoids, in addition to serving as a source of vitamin A, have been shown lo function as antioxidants. Studies show that lycopene. (

What are diastolic compressive forces, Q. What are Diastolic Compressive Fo...

Q. What are Diastolic Compressive Forces? Coronary perfusion pressure equal to pressure gradient between the coronary arteries and the pressure in LV in diastole. When coronary

The cell cycle, what happens to the liver cell during the cell cycle

what happens to the liver cell during the cell cycle

What is the functional unity of the kidneys, What is the functional unity o...

What is the functional unity of the kidneys? The functional (filtering) unity of the kidneys is the nephron. A nephron is made of afferent arteriole, efferent arteriole, glomer

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