S.3 Bio. Respiration And Gaseous Exchange Notes Caltec S.3

1 | P a g e CALTEC ACADEMY MA KERERE RESPIRATION AND GASEOUS EXCHANGE TISSUE RESPIRATION This is the breakdown of food substances to release energy. It occurs with the help of enzymes. The major food respired (respiratory substrate) is a carbohydrate (glucose). All other compounds are conve rted into a carbohydrate before they are respired. The energy released is stored as ATP (Adenosine tri phosphate). ATP is highly energy rich compound formed between a chemical bond between ADP (Adenosine di phosphate) and inorganic phosphate groups, i.e. ADP + Pi ATP If the energy stored as ATP is required by the body, ATP is suddenly broken down into ADP and Pi to release energy for the body activities i.e. ATP ATPase enz yme ADP + Pi + energy The energy released is used by the body for various activities i.e. Maintaining blood circulation Bring about breathing movement For producing sound Transmission of nerve impulses from one part to another. Synthesis of blood proteins Maintaining the constant blo od temperature Cell division either mitosis or meiosis leading to growth Active transport of materials into or outside the cell. Secretion of various materials like hormones, enzymes, etc. Stages of respiration Respiration occurs in a series o f reaction which are divided into 2 stages 1. Glycolysis It involves breaking down of six carbon compounds (glucose) into 2 small 3 carbon compounds. This occurs in the cell cytoplasm. 2. Krebs cycle It involves the breaking down of 3 carbon compounds further to release more energy than glycolysis. It occurs in the mitochondria. There are two types of respiration. 1. Aerobic respiration. 2. Anaerobic respiration AEROBIC RESPIRATION This is the breakdown of food to release energy in the presence of oxyg en. This type of respiration produces energy, Carbon dioxide and water. This is …