Tag: disorders of nervous system

Questions Related to disorders of nervous system

Which of the following is caused due to the formation of an opaque membrane once the eye lens?

evs we are special defects of eye disorders of nervous system braille script

  1. Presbyopia

  2. Astigmatism

  3. Cataract

  4. Myopia

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Correct Option: C
Explanation:

Cataract is a problem of an eye. It arises in old age it is caused due to the formation od an opaque membrane over the eyeless. This member reduces the intensity of light falling or the eye lens. Cataract is corrected by surgical replacement of lens with the artificial lens. 

Conjunctivitis is 

evs we are special defects of eye disorders of nervous system braille script

  1. The number of conjunctions in the english grammar

  2. The conjunction between ball and socket arrangement of human bones

  3. A common infection that affects our eyes

  4. A virus which attacks conjunctiva in the eyes

Show answer
Correct Option: C
Explanation:

Conjunctivitis is an infection of the eyes. In this the conjunctiva which is the thin skin present on the front of the eye becomes swollen. It may affect one or both eyes. The eyes become red and sticky or watery that causes eye surface irritation. So, the correct answer is option C.

Which of the following occurs in persons suffering from myopia?

evs we are special defects of eye disorders of nervous system braille script

  1. The eye ball is shortened

  2. Ciliary muscles contract

  3. The eye ball elongates

  4. The retina expands

Show answer
Correct Option: C
Explanation:

The shape of the lens of the eye is regulated by the suspensory ligaments and ciliary body. The focal length is adjusted by their regular contraction and relaxation. Myopia is a condition of the eye where light focuses in front, instead of on the retina. This causes distant objects to be blurry while close objects appear normal. Myopia is corrected by using a concave lens. This defect arises either by elongation of the eyeball of the excessive curvature of the cornea. In this far point of the suffering myopia cornea close to the eye.

Thus, the correct answer is option C.

In the myopia, eye defect, the light rays from iris

evs we are special defects of eye disorders of nervous system braille script

  1. Do not enter the eye at all

  2. Come to a focus at back of retina

  3. Come to a focus in front of the retina

  4. Come to a focus in between retina and iris

Show answer
Correct Option: C
Explanation:
Myopia is a visual defect in which distant objects appear blurred because their images are focused in front of the retina rather than on it. 
It's also termed as nearsightedness or short sight. This occurs when the eyeball becomes too long and prevents incoming light from focusing directly on the retina. It may also be caused by an abnormal shape of the cornea or lens. It is corrected with a spherical concave lens.

In the following abnormalities of the eye, which one is a serious condition that leads to blindness?

evs we are special defects of eye disorders of nervous system braille script

  1. Presbyopia

  2. Myopia

  3. Hypermetropia

  4. Glaucoma

Show answer
Correct Option: D
Explanation:

Loss of flexibility in crystalline lens with age causes presbyopia which includes focusing on the image behind the retina. Both hypermetropia and presbyopia cause the formation of blurry nearby images which can be corrected by wearing of the convex lens. Myopia is caused by elongation of the eyeball which results in focusing of the image in front of retina and forms blurry distant images. Myopia is corrected using the concave lens. Glaucoma is caused by blockage of tiny ducts that drain the excess aqueous humor from anterior compartment causing a buildup of aqueous humor. This causes compression of the arteries that serve the nerve fibers of the retina due to increased pressure. The death of nerve fibers due to lack of nutrients makes the person partially blind. Thus, the correct answer is option D.

The defect of eye develops in the old age because

evs we are special defects of eye disorders of nervous system braille script

  1. Lens becomes opaque

  2. Eye ball becomes small

  3. Eye ball becomes long

  4. Lens looses its elasticity

Show answer
Correct Option: D
Explanation:

Presbyopia is the defect of old age in which both the near and distant objects are blurred The elasticity of lens of eye decreases hence the accommodation power diminishes.

Astigmatism is corrected by the use of

evs we are special defects of eye disorders of nervous system braille script

  1. Convex lens

  2. Concave lens

  3. Cylindrical lens

  4. Surgery

Show answer
Correct Option: C
Explanation:

  • Convex lens converge the light rays and decrease the focal length.
  • Concave lens diverge the light rays and increase the focal length.
  • Cylindrical lens have curved surfaces that focus the light rays to a point.
Astigmatism occurs due to imperfection in curvature of eye due to which light rays are focussed inaccurately on the retina and this is corrected by using cylindrical lens.
So, the correct answer is 'Cylindrical lens'.

In old age, the vision of eye becomes dim. It is due to

evs we are special defects of eye disorders of nervous system braille script

  1. Myopia

  2. Hypermetropia

  3. Cataract

  4. Astigmatism

Show answer
Correct Option: C
Explanation:
A. Myopia occurs when eye ball becomes longer and it results in the formation of image in front of retina.
B. Hypermetropia occurs when eye ball becomes shorter and it results in the formation of image behind the retina. 
C. Cataract is an eye disease that occurs in older people. The visibility is reduced because the eye lens becomes opaque
D. In astigmatism, the vision gets blurred due to improper of eye's curvature.
So, the correct answer is 'Cataract'.

Concave lens is employed to correct _______.

evs we are special defects of eye disorders of nervous system braille script

  1. Presbyopia

  2. Hypermetropia

  3. Cataract

  4. Myopia

Show answer
Correct Option: D
Explanation:
A. Presbyopia occurs in the late age (generally after 40 years) due to loss of elasticity of eye lens due to which nearby objects are not correctly visible. It is corrected by using bifocal lengths.
B. Hypermetropia occurs when eye ball becomes shorter and it results in the formation of image behind the retina. It is corrected using convex lens which focus the light rays on the retina.
C. Cataract is an eye disease that occurs in older people. The visibility is reduced because the eye lens becomes opaque. It is treated by surgery.
D. Myopia occurs when eye ball becomes longer and it results in the formation of image in front of retina. It is corrected using concave lens which diverge the light rays to get focussed on the retina. 
So, the correct answer is 'Myopia'.

Reduction in elasticity of eye lens with age causes ________.

evs we are special defects of eye disorders of nervous system braille script

  1. Myopia

  2. Presbyopia

  3. Cataract

  4. Hypermetropia

Show answer
Correct Option: B
Explanation:
A. Myopia occurs when eye ball becomes longer and it results in the formation of image in front of retina. It is corrected using concave lens which diverge the light rays to get focussed on the retina.
B. Presbyopia occurs in the late age (generally after 40 years) due to loss of elasticity of eye lens due to which nearby objects are not correctly visible. It is corrected by using bifocal lengths.
C. Cataract is an eye disease that occurs in older people. The visibility is reduced because the eye lens becomes opaque. It is treated by surgery.
D. Hypermetropia occurs when eye ball becomes shorter and it results in the formation of image behind the retina. It is corrected using convex lens which focus the light rays on the retina.
So, the correct answer is 'Presbyopia'.