FLORA WORLD

  Nitrogen cycle Nitrogen cycle is a biogeochemical cycle through which nitrogen element is circulated continuously through the living and non-living components of the biosphere .   Air contains about 78% of nitrogen in the earth’s atmosphere. Nitrogen is an essential component of life but the abundant nitrogen in the atmosphere can’t be used directly by the plant or animals. Nitrogen gas exists in both organic and inorganic forms . Organic from of nitrogen exists in living organisms and passed through the food chain by the consumption of the other living organisms. Inorganic form of nitrogen found in the atmosphere. This nitrogen is available to plant in the form of nitrites and nitrates . Nitrogen cycle has the following steps: A.   Nitrogen fixation Nitrogen fixation is the process of converting nitrogen of the atmosphere into nitrogen compounds is called nitrogen fixation. It takes place in to following ways: 1.      Atmos...

  RESPIRATION IN HUMANS  What is respiration? Exchange of gases (CO 2 and O 2 ) and utilization of oxygen (O 2 ) to breakdown of food to release energy is called Respiration . Respiration is a catabolic process . The organs which help in different organism to respire are known as Respiratory organs . These organs work together called Respiratory system of an organism. In unicellular and lower multicellular organisms respiration occurs through general body surface. In higher multicellular organism there is a system which transports oxygen in each and every cell of the body. The process of respiration in higher animals involves two steps- 1.      External Respiration - ·         It involves breathing (inspiration and expiration) and gaseous exchange (O 2 and CO 2 ). ·         It involves respiratory organ like Lungs, trachea etc. ·       ...