FUNCTIONS OF PLANT PARTS
Fresh Water from a Plant
Tie a large plastic bag a tree branch that has a lot of leaves. Leave it for a few days.
It will collect the fresh water released by the leaves through a process called transpiration.
Collect Oxygen from Water Plants
- Safety Rules:
- Parent supervision
- Take care with fire or heat
- Materials you need are:
- pondweed (from a fish tank or a lake)
- a clear bowl
- a clear jar (smaller in diameter than the bowl)
- supports (e.g. cotton reels)
- matches
Set up the materials as in the diagram. Place the whole experiment where it gets enough light to photosynthesise but doesn't get too hot. Leave it for several hours. The oxygen should have collected in the upside-down jar. To test it carefully light a match and then lift the jar quickly, placing the lit match into the jar. If oxygen is present, the flame should get brighter for a short time.
In the process called photosynthesis, plants convert carbon dioxide gas and water in the presence of light and green chlorophyll to make sugar and oxygen gas.
Cheap Plant Propagation
- Plant various cuttings (e.g. geranium, chrysanthemum, carnation, rosemary, african violet, begonia, zygocactus) or tubers (e.g. potatoes with ‘eyes’) straight into a mix that is ½ peat and ½ sand.
- Put cuttings of other plants (e.g. coleus) into a jar of water for a week or so until many roots have appeared. Then plant them into the soil mixture.
What Makes Flowers Last Longer
- Safety Rules:
- Parent supervision
- Take care with aspirin and household bleach (They are poisonous)
- Wear gloves and goggles
- Materials you need are:
- several vases of the same size
- flowers of the same type
- an eyedropper
- gloves
- goggles
- various household chemicals (e.g. sugar, aspirin, household bleach)
Test what chemicals added to the water in a vase make flowers last longer. Use the same size of containers, the same amount of water, and the same type and number of flowers.To these, add the different chemicals - one chemical in each container. Try sugar, aspirin or even 4 to 5 drops of household bleach.
Because flowers decay due to bacterial decomposition, the chemical which kills bacteria but does not harm the flowers will probably be the best.
Extract Chlorophyll from Plant
- Safety Rules:
- Parent supervision
- Take care with a knife
- Take care with methylated spirits (It is flammable and poisonous)
- Materials you need are:
- a few plant leaves
- a small amount of methylated spirits
- a mortar and pestle or similar to crush leaves
- a spoon
- a container
- a strainer
Thoroughly crush the leaves and then add a small amount of methylated spirits to obtain a green mixture. Strain the mixture, keeping the green liquid. This contains chlorophyll.
By crushing the plant cells, you have exposed the green chlorophyll. The methylated spirits is used to dissolve the chlorophyll so it can be poured off.
Make a Terrarium
- Safety Rules:
- Parent supervision
- Take care with a knife
- Materials you need are:
- an empty clear softdrink bottle (the largest you can find)
- a sharp knife
- some soil
- some plants
- some water
Cut the softdrink bottle horizontally so that you can keep the hard opaque plastic base and also the clear plastic part inside the base. The hard opaque base will be where you put the soil and your garden plants. Water this and then cover it with the inner clear plastic dome. It should require little watering as it keeps a very humid atmosphere inside the dome.