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L. no:1-Teeth And Microbes, Hardwords:, 1) Temporary, 2) permanent, 3) Incisors, 4) Canines, 5) Decay, 6) Enamel, 7) Dentine, 8) Tartar, 9) Plaque, 10) bacteria, 11) viruses, 12) fungi, 13) protozoa, 14) gums, 15) floss, C] Tick the correct options:, 1) no, 2) 6, 3) enamel, D] Fill in the blanks with the help of the given words:, 1) twice, 2) calcium, 3) twice

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4) small, A] Oral Questions:, 1) We should eat raw vegetables and fruits because they make our gums and teeth strong., 2) Pneumonia, tuberculosis., B] Science Quiz:, 1) Canines, 2) plaque, E] Very short Answers:, 1) Microscope, 2) Fungus, 3) Four ( incisors, canines, premolars, molars), F] Short Ansuwer Questions:, 1) Bacteria are single celled microorganisms., 2) By the age of three, a child has a set of twenty teet h. This set of teeth is called milk teeth or temporary, teet h., 3) (a) Tooth decay is decaying of tooth enamel due to the formation of plaque., (b) We can learn to be a good friend, taking care of others and also taking care of our health from Nitika., G] Long Answer Questions:, 1) When we eat, small bits of food may stick between our teet h. When we do not brush our teeth properly, this, stuck food rots and our teet h get covered with a thin sticky layers of germs called plaque. This plaque reacts, with the sugar present in the food to produce acid which affects the tooth enamel and start decaying it. This, is called tooth decay. It causes holes or cavities in the enamel and Dentine. As a result, the nerves and t he blood, vessels in the pulp get exposed and we get a tooth ache., 2) Teet h are important to us in the following ways., (i) They give shape to our face., (ii) They help us bite and chew the food., (iii) They help us speak clearly.

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3) Each toot h has two parts - crown and root. The part of the tooth we see is the crown and the part inside the, gum is root. The outside white covering is called enamel. The layer inside the enamel that forms the main hard, part of the tooth is called dentine. The centre of the tooth is called pulp. Pulp is soft and has blood vessels, and nerves in it., Think And Answer:, 1) Sonu has white shining teeth because he always brushes his teeth properly. Monu has a yellow covering over, teeth due to the formation of tartar., 2) When Neha was a child she had temporary teeth or milk teet h. As the temporary teet h fell, new teet h, grew in their place. But her fat her who is an adult, has permanent teet h which do not grow if lost due to any, reason., PICTURE TALK., Name the following microbes :, 1) Bacteria, 2) Protozoa., 3) Fungi.