Metabolism - the intricate network of chemical reactions that occur within cells - sustains life and maintain many critical cellular functions. Metabolic pathways and processes play crucial roles in various essential activities, such as energy production, nutrient utilization, and waste elimination. One of the most fundamental metabolic pathways is cellular respiration. It involves the breakdown of glucose and other organic molecules with the use of oxygen to produce energy in the form of adenosine triphosphate (ATP). Cellular respiration takes place in three main stages: glycolysis, the citric acid cycle (Krebs cycle), and oxidative phosphorylation, with the latter two processes occurring in mitochondria. The first step of cellular respiration is glycolysis in the cytoplasm. During glycolysis, a molecule of glucose (a six-carbon sugar) is broken down into two molecules of pyruvate (a three-carbon compound) generating a small amount of ATP and NADH (nicotinamide adenine dinucleotide), which carries high-energy electrons to the next stages of cellular respiration. After glycolysis, pyruvate is transported into the mitochondria, where it undergoes further breakdown in the citric acid cycle. Each pyruvate is converted to acetyl-CoA, which enters the cycle and reacts with oxaloacetate to form citric acid. Through a series of reactions, the citric acid cycle produces more NADH, FADH2 (flavin adenine dinucleotide), and ATP. The final stage of cellular respiration, oxidative phosphorylation, takes place in the inner mitochondrial membrane. It involves the transfer of electrons from NADH and FADH2 to the electron transport chain (ETC), a series of protein complexes. As electrons move through the ETC, they create a flow of protons (H+) across the membrane, establishing an electrochemical gradient. The flow of protons back into the mitochondrial matrix through ATP synthase generates ATP. Lipids are essential components of human cells, serving as structural components of cell membranes and energy storage molecules. Lipid metabolism encompasses processes like lipolysis (the breakdown of triglycerides into fatty acids and glycerol), lipogenesis (the synthesis of new lipids), and beta-oxidation (the breakdown of fatty acids to produce ATP). Carbohydrates are a primary source of energy for human cells. Glucose, obtained from the breakdown of carbohydrates, is used to produce ATP through cellular respiration. Excess glucose is stored as glycogen in the liver and muscles, which can be broken down into glucose units when energy demands increase. As a result of various metabolic processes, human cells produce waste products such as carbon dioxide, urea, and ammonia. These waste products must be efficiently eliminated to maintain cellular homeostasis. Carbon dioxide is expelled through respiration, whilst urea and ammonia are filtered by the kidneys and excreted in urine. We offer a large product range of research tools for studying pathways and processes, including Bcl-2 antibodies, Transferrin Receptor antibodies, GAPDH antibodies, Adiponectin ELISA Kits, and Myeloperoxidase ELISA Kits. Explore our full pathways and processes product range below and discover more, for less. Alternatively, you can explore our Metabolic Signaling Pathways, Metabolism Processes, and Mitochondrial Metabolism product ranges.