Cells and Chemical Reactions: Photosynthesis

Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the second of four Science Objects in the Cells and Chemical Reactions SciPack. It investigates the process of photosynthesis and the chemical reactions that take place in plant cells.

Photosynthesis involves unique synthesis chemical reactions in which energy from the sun is transferred into energy in the chemical bonds that are formed when smaller molecules are combined to synthesize complex molecules. For nearly every living organism on Earth, the energy required by its cells originally comes from the sun and the only way to transfer light energy into living systems is through photosynthesis. Only those organisms with chlorophyll, such as plants, can capture energy by absorbing light and using it to form strong (covalent) chemical bonds between atoms of carbon-containing (organic) molecules through photosynthesis. Plants have chlorophyll contained in chloroplasts (the site of photosynthesis) where energy rich organic compounds are synthesized for use by the plant as a source of matter and energy necessary for life. This process of photosynthesis provides a vital connection between the sun and the energy needs of nearly all living systems, and also releases oxygen to the environment.

The simple carbohydrates produced during photosynthesis can be decomposed immediately to supply matter and energy needed for metabolic processes by plants or other photosynthesizing organisms. In addition, the energy from the decomposition can be used to build other complex carbon-based molecules that help the plant grow and function (including proteins, lipids and more complex carbohydrates).


Elementary SchoolMiddle SchoolHigh School


Type Science Object

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