Interdependence

Harvesting The Sun

• Plants capture energy from sunlight, many complex chemical reactions are involved. 
• Plants use energy from sunlight to build up carbon dioxide and water into organic compounds such as glucose, this is the process of Photosynthesis.
• Energy from the sunlight is transferred to chemical energy in the new compounds, So these compounds act as an energy store. 
• They can be used as food molecules which are broken down to release energy, they also provide raw materials to build new plant cells for growing.
• Living things that can make their own food are called Autotrophs.
• Organisms that rely on other living things for food are called Heterotrophs.

Trapping Light Energy

• Less than one-billionth of the sun's energy reaches the plants on earth.
• Plants only convert only about 1-3% of this light energy into new plant material.
• 60% of the light is the wrong wavelength for photosynthesis.
• 5% Passes straight through the plant.
• 35% is absorbed by the chloroplasts.
• 2% is transferred to organic materials.
• 33% is transferred as waste heat.
• The chemical equation for photosynthesis: 

6Co2 + 6H2O => C6H12O6 + 6CO2

• A glucose molecule is made up of carbon, hydrogen, and oxygen atoms. So glucose is a carbohydrate.
• Photosynthesis takes place in Chloroplasts, they contain a green pigment called chlorophyll.
• Chlorophyll absorb light and uses the energy to kick start photosynthesis. 
• The light energy splits water molecules into hydrogen and oxygen atoms. 
• The hydrogen is combined with carbon dioxide from the air to make glucose.
• The oxygen is released as a waste product, it passes out of the plant and into the air.
• Given enough raw materials, light, and the right temperature, a large tree can ,make 2000kg of glucose a day.

Using glucose from photosynthesis

• Like all larger living things, plants are made up of different types of cells, but every cell is made up of the same basic chemicals:
• Cell wall: Made of cellulose- a carbohydrate.
• Membrane: Made…