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Author: Tamara Poulos

This is a tutorial explaining the process and steps of photosynthesis.
This tutorial's topic covers the California State Standards Grade 3: Physical Sciences: Energy and Matter have multiple forms and can be changed from one form to another. 
1a. Students know energy comes from the Sun to Earth in the form of light. 
1b. Students know sources of stored energy take many forms, such as food, fuel and batteries.
1c. Students know machines and living things convert stored energy to motion and heat.
1d. Students know energy can be carried from one place to another by waves, such as water waves and sound waves, by electric current, and by moving objects.
1g. Students know that when two or more substances are combined, a new substance may be formed with properties that are different from those of the original materials.
1h. Students know all matter is made of small particles called atoms, too small to see with the naked eye.

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Before You Start

Were you aware of how important Photosynthesis actually is to living beings?

Think About It

Photo synthesis provides oxygen to the atmosphere. We as humans and are fellow animals need oxygen to breath and live.

Terms to Know

Photosynthesis - process in which green plants and various other organisms use the energy from the sunlight to produce food from carbon dioxide and water. 
Ecosystem - a biological community of interacting organisms in their physical environment.
Carbon Dioxide - a color-less and order less gas that is produced by burning carbon and organic compounds.
Stomata -(plural noun of Stoma) are pores in leaf or stem of a plant.
Chlorophyll - a green pigment that is present in plants that are green and in cyanobacteria. 
Atmosphere - The gases surrounding the earth or other plants.
Glucose - a sugar that provides energy and is found in many carbohydrates.
Calvin Cycle - a set of chemical reactions take place in chloroplasts during photosynthesis.

Big Idea

The process of photosynthesis is very important to the ecosystem.
Photosynthesis is the process of plants making their own nutrients to survive.

Plants need: Water, Sunlight and Carbon Dioxide
We cannot see the atoms or particles because they cannot be seen by a naked eye and need to be viewed by a microscope or other form of in-depth 


Photo Credit:


On a plant, the carbon dioxide comes into the leaves through holes called a stomata. Then the water is absorbed by the roots in the ground and travels up the stem to the leaves. The sunlight is then absorbed by chlorophyll (that makes them green) that is in the leaves.

Did You Know

The world chlorophyll comes from the Greek words χλωρός, chloros and  φύλλον, phyllon.

The energy that chlorophyll absorbs is then used to split the water molecules into two forms: hydrogen and oxygen.

The oxygen is released through the leaves into the world's atmosphere. While the hydrogen and carbon dioxide form glucose as a source of food for the plants.

Concept to Know
Forming the nutrients to survive or food for plants is a 4- step process.
The first step is the absorption of light. 
The second step is the electrons transportation making NAD P+ to NADPH.
The third step is the generation of ATP.
The fourth step is the conversion of CO into carbohydrates.
There are two stages of photosynthesis, which is the light-dependent reactions and the Calvin cycle. The light-dependent reactions form NADPH and ATP.

Learn More

To learn more about the two stages follow the link to the youtube video titled Nature's smallest factory: The Calvin cycle - Cathy Symington.

Concept to Know

The equation for photosynthesis is shown in the image below. The combination of carbon dioxide, water and the energy from light then works together to produce a carbohydrate called glucose and oxygen. 


The formula is 6 C O subscript 2 plus 6 H subscript 2 O space plus space l i g h t space e n e r g y space equals space C subscript 6 H subscript 12 O subscript 6 plus 60 subscript 2


Photo Credit: 


Photosynthesis is a process that plants go through to make food for themselves that in turn provides oxygen for the atmosphere that we need to live. There is a formula: 6 C O subscript 2 plus 6 H subscript 2 O space plus space l i g h t space e n e r g y space equals space C subscript 6 H subscript 12 O subscript 6 plus 60 subscript 2 of this process. There is also a 4-step or 2 stage description of this process. The two stage process is light-dependent reactions and the Calvin cycle. The four steps is absorption of light, electrons transport to make NAD P+ to NADPH, the generation of ATP and the conversion of CO into carbohydrates. Plants need the glucose that comes from this process and humans need the oxygen that come from this process. 

Helpful video of this information:

Additional links helpful on the topic:

Artificial Photosynthesis:

The Discovery of Photosynthesis: