We all need energy to function and we get this energy from the foods we eat. The most efficient way for cells to harvest energy stored in food is through cellular respiration, a catabolic pathway for the production of adenosine triphosphate (ATP). ATP, a high energy molecule, is expended by working cells.
An Apple a Day. The calories in a McIntosh apple depend on its size. According to the U.S. Department of Agriculture, a medium-sized apple with its skin has about 95 calories. Eating an unpeeled apple is moderately higher in calories than a peeled apple, but don't rush to peel your apple.
A medium sized apple available at Publix also contains 80 calories. It also contains 1 gram of fat content, 165 mg of potassium and 21 grams of carbohydrate content. Out of these 80 calories 90% of the calories come from carbohydrates and the remaining 10% come from fat. How many Calories in a Juiced Green Apple.