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=PHOTOSYNTHESIS= Photosynthesis is the process by which plants and other things make food.It is a chemical process that uses sunlight to turn carbon dioxide into sugars the cell can use as energy. As well as plants, many kinds of algae, protists and bacteria use it to get food.

Factors affecting photosynthesis
There are three main factors affecting photosynthesis:

Light intensity Carbon dioxide concentration Temperature

Light intensity
If there is little light shining on a plant, the light-dependent reactions will not work efficiently. This means that photolysis will not happen quickly, and therefore little NADPH and ATP will be made. This shortage of NADPH and ATP will lead to the light-independent reactions not working as NADPH and ATP are needed for the light-independent reactions to work.

Carbon dioxide levels
Carbon dioxide is used in the light-independent reactions. It combines with NADPH and ATP and various other chemicals (such as Ribulose Biphosphate) to form glucose. Therefore, if there is not enough carbon dioxide, then there will be a buildup of NADPH and ATP and not enough glucose will be formed.

Temperature
There are many enzymes working in photosynthetic reactions - such as the enzyme in photolysis. These enzymes will not work as well, or stop working at all at high or low temperatures and therefore, so will the light-dependent and light-independent reactions

The process of photosynthesis
Photosynthesis is the process that plants use to change the energy from sunlight into energy for food. Plants change light energy from the sun into food energy. Photosynthesis happens in all green parts of a plant. Leaves are usually the greenest parts. So plants do this mostly in their leaves. There are some important requirements for photosynthesis to happen:

Chlorophyll
Chlorophyll is a green substance that plants use to capture light energy from the sun. Chlorophyll is very important. Without chlorophyll plants cannot use the sunlight energy to make food. Also, oxygen levels in the air will go down. If that happens plants and animals will suffocate.

Sunlight
Sunlight has energy. Plants use this energy to make sugars from water and carbon dioxide.

Water
The roots of a plant absorb water and nutrients from the soil. Water is a solvent in all living things. Dissolved substances are moved around the body to where they are needed. Just like you, plants have veins for this movement. They move minerals from the roots upwards. They move sugars from the leaves downwards. Photosynthesis can only happen in a water solution. Water is also important because it provides support to the plant to keep it upright. Like you, plants have skeletons. But unlike you many plants have water skeletons!

Carbon dioxide
The plant absorbs or takes in carbon dioxide from the air through little holes. These holes are found all over the plant, mostly under the leaves.

Soil
The soil provides mineral nutrients and water for the plant that are necessary during photosynthesis. Soil also provides anchorage to the plant, otherwise the plant cannot stand up straight.