What is the fuel for the cells of the body?

What is the fuel for the cells of the body?

• A. NADH
• B. ATP
• C. Glucose
• D. Amino acids

Answer: (B)

Energy for cellular work comes from ATP, the body's immediate energy currency. Cells generate ATP through metabolic pathways that transfer energy from nutrients to ATP. When a cell needs to do work, it breaks a phosphate bond in ATP, releasing energy and turning it into ADP and a phosphate. That released energy powers processes like muscle contraction, nerve signaling, and transport across membranes. NADH plays a supporting role as an electron carrier that helps produce ATP, but it isn’t the direct fuel used for work. Glucose provides the raw energy source that ultimately yields ATP, yet the actual energy used at any moment is stored in ATP. Amino acids can be used for energy or to build proteins, but they’re not the primary fuel under normal conditions.

Energy for cellular work comes from ATP, the body's immediate energy currency. Cells generate ATP through metabolic pathways that transfer energy from nutrients to ATP. When a cell needs to do work, it breaks a phosphate bond in ATP, releasing energy and turning it into ADP and a phosphate. That released energy powers processes like muscle contraction, nerve signaling, and transport across membranes. NADH plays a supporting role as an electron carrier that helps produce ATP, but it isn’t the direct fuel used for work. Glucose provides the raw energy source that ultimately yields ATP, yet the actual energy used at any moment is stored in ATP. Amino acids can be used for energy or to build proteins, but they’re not the primary fuel under normal conditions.