Metabolism and Energy Essay

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Metabolism is defined the sum of all chemical reactions which occurs and are involved in sustaining life of a cell, and thus an organism. Metabolism is of the following two types: catabolism and anabolism. In catabolism, molecules break down producing energy
During anabolism, synthesis of essential compounds needed by the cells are produced (such as DNA, RNA, and protein synthesis).
Bioenergetics describes the metabolic pathways by which a cell obtains energy. Nutrition science studies the relation between food substance and living things. The study deals with:
1) Body requirements of various substances.
2) The function of various substances in body.
3) The amount of the substances needed.
4) The lower levels below which health gets
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MECHANISM OF ATP SYNTHESIS
Energy metabolism is the process by which living cells obtain energy and use them to live, grow and reproduce. Energy is released when the chemical bonds of the nutrient molecules break and form high energy compounds such as ATP. ATP is the main chemical energy carrier in all the cells. ATP synthesis can occur by two mechanisms:
1) Synthesis from ADP and inorganic phosphate that takes place in mitochondrion.
2) Synthesis by transfer of high energy phosphoryl groups from high energy compounds to ADP. The synthesis occurs in both mitochondrion and in cytoplasm.
OXIDATIVE PHOSPHORYLATION: THE MAIN MECHANISM OF ATP SYNTHESIS IN MOST HUMAN CELLS
In the metabolic reactions, oxidation-reduction reactions are very essential for ATP synthesis. The electrons removed in the oxidation are transferred to two major electron carrier enzymes. The electrons are transported through protein complexes in present in the inner mitochondrial membrane. The complexes contain attached chemical groups which are capable of accepting or donating one or more electrons. The protein complexes are known as the electron transfer system (ETS). The ETS allow distribution of the free energy between reduced coenzymes and the O2. The ETS is associated with proton (H+) pumping from the mitochondrial matrix to intermembrane space of the mitochondria.
TRICARBOXYLIC ACID CYCLE (TCA)
The tricarboxylic acid cycle is known as Krebs cycle, named after Sir…