CBSE ADDA

CBSE _ NCERT Class-7th Science   Chapter:  Fibre to Fabric Why a cotton garment cannot keep us as warm in winter? Cotton clothes are thin and do not have spaces in which air can be trapped. thus Cotton clothes do not prevents heat coming out of our body. What is a fibre? A fibre is a long strong thread, which is obtained from natural sources or man made sources. Fibres are classified into two types on the basis of their sources. Plant fibres and animal fibres and synthetic fibres . The fibres, which are obtained from plants and animals are called natural fibres e.g., jute and wool. Animal   fibres are obtained from animals, e.g., silk and wool. Those fibres which are made by the human –beings are known as Man-made or Synthetic Fibres, e.g., Rayon. Match the following: 1. Scouring-- >            Cleaning sheared skin 2. Mulberry leaves ->   Food of silkworm 3. Yak ->                   Wool yielding animal 4. Cocoon ->              Yields sil

Nutrition in Plants Solved question Answer Fill in the blanks: (a) Green plants are called _        autotrophs __ since they synthesize their own food. (b) The foods synthesized by the plants are stored as starch  . (c) In photosynthesis solar energy is captured by the pigment called ___ chlorophyll (d) During photosynthesis plants take in ____ CO 2 ________ and release _ O 2 Name the following: (i) A parasitic plant with yellow, slender, tubular stem.-------   Cascuta (ii) A plant that has both autotrophic and heterotrophic mode of nutrition.---------   Insectivorous  plants (iii) The pores through which leaves exchange gases. ------- Stomata (iv)   A plant that has both autotrophic as well as heterotrophic mode of nutrition. --- Pitcher plant. (v)   An organism that live is an association of an alga and a fungus     ---------- lichen (vi)   Amarbel is an example of: ---- parasites   (vii) The plant which traps and feeds on insects is-----