Additional Questions And Answers
Ques: What is cornia?
Ans: Outer coat of the eye is white. Its transparent front part is called cornea.
Ques: What is iris? Write the function of iris?
Ans: Behind the cornea, we find a dark muscular structure called iris.
Function;
(i) The iris controls the size of the pupil.
Ques: Give regions;
(i) The outer most covering of eyes are white and hard.
Ans: As it can prevent the inner most part of eyes by accidents.
Ques: Differentiate between regular and diffused reflection. Does diffused reflection mean the failure of the laws of reflection?
Ans:
Irregular reflection |
Regular reflection |
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|
No, diffused reflection is not due to the failure of the laws of reflection
Ques: Fill in the blanks in the following :
(i) A person 1 m in front of a plane mirror seems to be __1__________ m from his image.
(i) If you touch your ____________ ear with right hand in front of a plane mirror it will be seen in the mirror that your right ear is touched with ____________ .
(iii) The size of the pupil becomes ____________ when you see in dim light.
(iv) Night birds have ____________ cones than rods in their eyes..
Que: Draw a labeled sketch of the human eye.
Ans:
Ques: What is blind spot?
Ans: At the junction of the optic nerve and the retina, there are no sensory cells, so no vision is possible at that spot. This is called the blind spot.
Ques: write kinds of optic nerves.
Ans: There are two kinds of nerve cells
(i) Cones, which are sensitive to bright light.
(ii) Rods, which are sensitive to dim light.