Forests: Our Lifeline There are three major types of forests- tropical, temperate and boreal forests. Forest profile There are different kinds of plants of varied height and size in the forests. Parts of a tree above the stem, including the branches and leaves are collectively known as the Crown. Trees belonging to the genus Pinus […]
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Wastewater Story Water – Our Lifeline Sewage Types of Impurities Examples Organic impurities Human faeces, animal wastes, oil, urea, pesticides,herbicides, fruit and vegetable wastes Inorganic impurities Nitrates, phosphates, metals Nutrients Phosphorus and nitrogen Bacteria Those which cause diseases such as cholera, dysentery andtyphoid Sources of wastewater: Treatment of sewage in cities and towns: If sewage
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Reproduction in Plants Asexual Reproduction Vegetative Propagation (a) Vegetative Propagation by Stems The stems (or branches) of plants normally bear buds in the axils which can be used in vegetative propagation to produce new plants. New plants can be obtained from the stem (or branch) of an existing plant by the method of cuttings. A
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Transportation in Animals and Plants Circulatory System Blood plasma. Blood Vessels Heart The arteries and veins in the heart connect to other parts of the body. The blood vessels that enter or leave the heart are: Vena cava: It is a large vein that collect blood rich in carbon dioxide from all parts of the
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Respiration in Organisms What is Respiration? Anaerobic Respiration in Muscles We (human beings) normally obtain energy by aerobic respiration. But under certain conditions (when extra energy is needed), anaerobic respiration can take place in our muscles for a short time. When the oxygen gets used up faster in our muscle cells than can be supplied
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Nutrition in Animals INTRODUCTION Animals get their food from plants, either directly by eating plants or indirectly by eating animals that eat plants. Some animals eat both plants and animals. Recall that all organisms including humans require food for growth, repair and functioning of the body. Animal nutrition includes nutrient requirement, mode of intake of
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Nutrition in Plants What is Nutrition? Autotrophic It is a mode of nutrition in which organisms prepare their own food. Inorganic molecules like CO2 and H2O are converted into organic molecules like carbohydrates in the presence of sunlight and chlorophyll. E.g. Green plants. Autotrophs are further categorized as: Photosynthesis Importance of Photosynthesis Synthesis of Plant
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