The three main nutrients used for energy are carbohydrates, protein, and fats, with carbohydrates being the most important source. Your body can also use protein and fats for energy when carbs have been depleted. When you eat, your body breaks down nutrients into smaller components and absorbs them to use as fuel.
B) lipids since I saw this answer before
Diffusion is important to the cell because it is the process by which useful molecules enter the cell and waste products removed from the cell.
Without diffusion, cells and tissues of the body can not get important nutrients and gases for survival and would die.
An example is the eye. The eyes lack a great number of blood vessels (which carry oxygen that diffuses into cells) and must have an extra supply of oxygen. The atmosphere provides the extra needed oxygen which is taken up into the cells of the eye by diffusing through the cornea and thus the eye is kept functioning. If this does not happen , the eye would dry out.
All living things are made up of cells. Cells is the most basic unit of life. And cells must come from preexisting cells. Rudolph Virchow, Theodore Schwan, and Matthias Schelieden. Hope this helps.
