Human eye and coluorful world basic questions for class 10 SA2

By Muhammad Sahanawaj Fill in the blanks1. The transparent spherical membrane coveringthe front of the eye is called ____________. 2. _______ is the surface which acts as screen and image is formed on it. 3. The coloured diaphragm between cornea and lens is known as __________. 4. A small hole in iris which controls the intensityof light entering the eye is called __________. 5. ____________ muscles hold the position of the lens and adjust its thickness. 6. The point on retina at which optic nerve leavesthe eye is called ___________. At this point if any image formed is not sent to the brain. 7. A point on retina which has highest concentration of sensitive cells and forms a clearimage when we see any object minutely, is called __________. 8. The ability of eye lens to focus near and far objects clearly on retina by adjusting is focal length is called the _______________ of the eye. 9. For a young human adult with normal vision, the near point is about ___________ and it is denoted by ______. 10. For a young human adult with normal vision, the far point is at __________. 11. To see objects with both eyes together is called _________ vision. 12. A transparent alkaline liquid between cornea and lens is called ___________. It helps in ________ of light rays in cornea. 13. A jelly fluid filling the space between lens and retina is called _________. It with stands atmospheric pressure and prevents eye ball fromcollapsing. 14. Human is made up of ___________ jelly fluid material and it is a _________ __________ lens. 15. In __________ distant objects are not clearly visible. It is corrected by using ________ lens. 16. In ___________ objects nearby are not distinctly visible. It is corrected by using _______ lens. 17. ________ occurs due to weakening of ciliary muscles in old age. It can be corrected by using __________ lenses. 18. Power of a spherical lens is the reciprocal value of its _______________. Answers:1: cornea2: retina3: Iris4: pupil5: Cilliary6: Blind Spot7: Macula or yellow spot.8: accommodation9: 25 cm, D10: infinity (∞)11: binocular12: aqueous humour, refraction13: vitreous humour14: crystalline, double, convex15: myopia, concave16: hypermetropia, convex17: Presbyopia, bi-focal18: focal length