Plants need to eat as well! But there is a problem, plants can’t move around to find their food like most animals can. To get around this, they have developed a way of making their own food called photosynthesis.
So how do they do it? Well, it’s 2 main sections. Stage 1 is when the green coloured substance - chlorophyll, found in the chloroplasts of plant cells - traps light. This light energy is used to break apart water to make just hydrogen and oxygen (because water is made of hydrogen and oxygen). The oxygen is spat out as a waste product because it is not needed by the plant. However, organisms need oxygen to be able to do respiration, and so humans, animals and even plants use it again in respiration.
Once they have this, it then moves onto stage 2, where the hydrogen is combined with carbon dioxide to make glucose. Glucose provides energy for growth of the plant and it is also stored as starch for later use, because starch does not dissolve in water.
So you need to know the word equation. Seriously – they ask you to fill in the blanks and it can be worth 2 marks – remember it!
You also need to know the balanced symbol equation for photosynthesis - are you ready?
6CO2 + 6H2O -> C6H12O6 + 6CO2
In order for plants to grow, glucose is turned into cellulose to make new cell walls. Vegetable fats and oils are also made of glucose and stored for future use. We extract them from plants and use them for cooking.