Answer:
Phosphorus in ATP (Adenosine Triphosphate) comes from various sources, including food and cellular metabolic processes. Inorganic phosphate (Pi) is an essential nutrient in many foods, such as meat, fish, dairy, and whole grains. When we consume these foods, the phosphate is broken down and absorbed by the body, which can then be used to synthesize ATP in the cells.
Furthermore, the cellular metabolic processes, such as the breakdown of glucose, release Pi, which can be recycled to make more ATP. During cellular respiration, glucose is broken down into pyruvate, and Pi is released as a byproduct. This Pi is then used to replenish the phosphate groups in ATP, essential for energy transfer within the cells.
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