The ocean is a remarkable watery world, but it has its limits. The ocean is not self-cleaning. It takes help from the animals and plants that live in it to keep it clean.

The oceans are vast, but they are not limitless. They have their own ecosystems, just like land animals and plants do. These ecosystems are called food chains because each living thing depends on something else for food and energy. There are many different types of food chains in the ocean, but they all start with plants that photosynthesize their food from sunlight and carbon dioxide (CO2).

Photosynthesis is the process by which green plants use energy from sunlight to convert CO2 into carbohydrates using chlorophyll molecules in their leaves as part of this process. Some of these carbohydrates are used by the plant itself; some are stored as starches or sugars; while others may be used by other organisms such as animals or bacteria that feed on them. Some marine plants also produce oxygen as a result of photosynthesis (photosymbiosis) and release it into the water where other organisms can use it for respiration (oxygenating).

Once you understand how photosynthesis works in terrestrial (land) plants, you will be able to understand how it works in aquatic plants.

Last modified: September 20, 2022