Photosynthesis - Worksheet for Gr 5-7

Green plants produce their own food through a process called photosynthesis.

Plants do not have to wait on animals or people to feed them, they can make their own food whenever they need it.

To make food, plant will need carbon dioxide, water and sunlight.

The plant collects these three things in different ways:

• Carbon dioxide from the air passes through small holes in the leaves called stomata

                                    

image source

• Water is absorbed by the roots and moves through the stem to the leaves
• Sunlight is absorbed by organelles in the cells of the leaves called chloroplasts - it has a green substance/chemical in it called chlorophyl, where photosynthesis takes place.  Chlorophyl also gives the plant its green colour

                

image source

• what is the process called through which plants make their own food?
• which 3 things does a plant need/take up from around it for photosynthesis to take place?
• what is the function of the stomata?
• which organelle in the cells of the leaves plays a huge part during photosynthesis and what substance is found inside this organelle?

The process of photosynthesis

• The chlorophyl in the leaves absorbs the sunlight
• this energy from the sun splits the water molecules into hydrogen and oxygen
• carbon dioxide is taken up by the leaf and it and the hydrogen is used to make glucose which is the food of the plant and will be stored until it is needed
• the oxygen is given off in the atmosphere
• some of the in the stem, the leaves or the roots and some are used to make the plant grow 

• look at the sketches below and try and explain in your own words what happens during the photosynthesis process

                    

image source

You can also watch the following video to make sure you understand the whole process

Why is photosynthesis important?

It provides two important things.  Food and oxygen.

Some of the glucose is stored in the roots and fruits.  That is why we can eat carrots, apples, watermelons, potatoes etc.  These foods provide energy for humans and animals.

Oxygen is released in the atmosphere and we need to inhale oxygen to live.

Photosynthesis is also necessary to balance the oxygen and carbon dioxide levels in the atmosphere.

• which 2 important things does photosynthesis in plants provide?
• why do we need oxygen?
• what do we get from the plants we eat?