Although many of the approximately 200 cell types in the hum

Although many of the approximately 200 cell types in the human body can utilize all three major classes of food molecules for energy, not all can. Why? Provide an example.

Solution

There are about 200 cell types in human body and these cells use 3 types of food molecules such as carbohydrates, proteins and lipids to produce energy. Some cells are able to utilize all three types of food molecules and some cells use only specific types of food molecules to produce energy. Cells utilize food molecules depending on the type of enzymes they produce to breakdown the food molecules. For example, lipase produced in pancreas is required to breakdown fats. Muscle cells utilize glucose and obtain it from breaking down the muscle glycogen. Liver cells can utilize glucose and proteins because they contain enzymes that can metabolize glucose and proteins.