Class 10 Science notes

2 Mark Questions 1. Give scientific terms for the following- (a) the process of eating and being eaten (b) the relationship between abiotic and biotic component Ans. (a)  Food chain (b)  Ecosystem 2. What is meant by environment? Name its components. Ans.  The aggregate of all external conditions and their influences affecting the life and the development of an organism in its natural habitat is environment. It has two components- (1)  Abiotic components (non-living): For example- air, water, soil, temperature, etc. (2)  Biotic components (living): For example- Plant, animals and micro-organisms. 3. What is 10% law? Give an example Ans.  According to 10% law only 10% of energy is available at the next trophic level. For example- If energy available at producer level is 1000J then at next level only 10% of 1000J i.e. 100J is available. 4. What is artificial ecosystem? Give two examples. Ans.  Man-made ecosystem are called artificial ecosystem. For examp...

CHAPTER-11 HUMAN EYE AND COLORFUL WORLD Human Eye:  working of human eye, Persistence of vision, Power of accommodation of human eye, Defects of vision. The Human Eye:  It is a natural optical instrument which is used to see the objects by human beings. It is like a camera which has a lens and screen system. Structure of the Human Eye The various parts of eye and their functions : Retina: It is a light sensitive screen inside the eye on which image is formed. It contains rods and cones. Cornea: It is a thin membrane which covers the eye trail. It acts like a lens which refracts the light entering the eye. Aqueous humour: It is fluid which fills the space between cornea and eye lens. Eye lens: It is a convex lens made of transparent and flexible jelly like material. Its curvature can be adjusted with the help of ciliary muscles. Pupil: It is a hole in the middle of iris through which light enters the eye. It appears black because light falling on it goes into the eye and does n...