Science

Cells and Photosynthesis

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One of the most important characteristics about cells is the way in which they get food. Food is important because it is a cell's source of energy. The main purpose of food is to supply energy so that cells have the fuel to carry out their necessary functions. There are really only two ways to get food. A cell can make its own food or get it from somewhere else.

Animal cells must take food in from some other source. Plants, on the other hand, have the ability to make their own food through a process called photosynthesis. The word photosynthesis comes from two Greek words.

photo(light) + syntithenai(to put together) = photosynthesis

Photosynthesis is a process that takes place in the chloroplasts. It allows plants to build molecules of food by trapping the energy in sunlight. In essence, the plant cell uses the energy in sunlight to combine carbon dioxide and water to make molecules of glucose and to release oxygen.

Glucose is a carbohydrate that is a great energy source for cells. The energy from the sun becomes "trapped" in the glucose. Now, whenever the cell needs energy for one of its functions, it can break apart a molecule of glucose and get it.