How to Compare Photosynthesis in Plants & Bacteria

Plants release oxygen as part of the photosynthetic process.

Both bacteria and plants engage in photosynthesis--the process of converting light energy to a more usable form. The process is quite different in bacteria than it is in plants, but with a basic understanding of photosynthesis you can adequately compare the two.

Instructions

1. Notice the similarities in all photosynthetic processes. All photosynthesis involves converting light energy into cellular energy. More specifically, both plant photosynthesis and bacteria photosynthesis convert energy absorbed from sunlight into adenosine triphosphate (ATP), which is used to fuel cellular activity. Green plants and bacteria also both use carbon dioxide in the photosynthetic process.

2. Branch off from the similarities to compare how plants and bacteria differ. For example, while both plants and bacteria use carbon dioxide, plants require water to engage in photosynthesis while bacteria use molecular hydrogen and other inorganic compounds.

3. Examine the byproducts of photosynthesis. Plants generate oxygen and release it into the atmosphere while bacteria do not. This leads to the conclusion that bacteria engage in fermentation, which is itself a by-product of anaerobic respiration.

4. Study different types of bacteria. Some bacteria are considered purple rather than green and do not contain any chlorophyll. These bacteria perform photosynthesis in the least similar manner to plants, as plants use chlorophyll in the photosynthetic process.

References

• National Institutes of Health: Photosynthetic Mechanisms in Bacteria and Plants--Development of a Unitary Concept