Remember, as a member of the Science Bus Club you can ‘Ask Albert’ a question about any of the topics. So if you’re not already a member join today!!
Plants For Food
Yes humans do eat plants. Yum! They are full of goodness (vitamins & minerals) essential for healthy living. Do you like vegetables? Try to list as many vegetables and plants as you can.
Grow Some Plants
Have you ever grown a plant? When you do you will see it grow and grow. How does it grow?
Plants need five things to grow:- (1) light, (2) water,
(3) soil, (4) warmth and (5) air.
Green plants need light to grow and because of this they will grow towards the light to make sure that they get enough. Plants make food (sugar) in their leaves, using mainly sunlight, air and water. When plants don't get enough light they may turn yellow.
Green plants need soil to grow. Soil provides support for plants so they don't get washed or blown away. Water and nutrients, such as potassium, are absorbed from the soil by the roots and carried up the plant. The condition of the soil affects plant growth and what types of plants can grow in it. Plants that don't have enough soil are usually smaller than they should be as they are not getting the nutrients they need.
Green plants need air to grow and produce food. A gas in the air (carbon dioxide) is absorbed by tiny holes in the plant's leaves. It is used by the plant to produce food within the leaves and to produce oxygen. Plants make nearly all the oxygen we humans need to live.
If you have any more questions why not ask Albert?
Roots
Roots grow into the ground; how do they know to grow down when the rest of the plant grows up?
Plants are affected by gravity, so they do know which way is up and which way is down. Plants also know that water is found down in the ground and sunlight is found up in the sky. All plants need water and sunlight. The roots of a plant will always grow down to find water and the stem will always grow up to find sunlight so the plant can produce food through photosynthesis. If you have any other questions ask Albert!
Experiment With Celery
Here is an experiment to do with celery.
Take two glasses and half fill them with water.- Ask your Mum for some food colouring and put a few drops into ONE of the glasses.
- Then put in a stick of celery in each and leave for a few days.
What do you observe happening after a day or two? Ask Albert how this happens and why? Why did we have a glass with clear water in?
Roots
What do leaves do and why do most of them fall of in Autumn?
As summer ends and autumn comes, the days get shorter and shorter. This is how the trees "know" to begin getting ready for winter. During winter, there is not enough light or water for photosynthesis. The trees will rest and live off the food they stored during the summer. They begin to shut down their food-making factories.
The green chlorophyll disappears from the leaves. As the bright green fades away, we begin to see yellow and orange colours. Small amounts of these colours have been in the leaves all along. We just can't see them in the summer, because they are covered up by the green chlorophyll.
The bright reds and purples we see in leaves are made mostly in the autumn. In some trees, like maples, glucose is trapped in the leaves after photosynthesis stops. Sunlight and the cool nights of autumn cause the leaves turn this glucose into a red colour. The brown colour of trees like oaks is made from wastes left in the leaves. It is the combination of all these things that make the beautiful colours we enjoy in the autumn.
Stems are like a straw, they are used to
transport water through the plant. They also raise the height of flowers and leaves which brings the plant closer to the light.
The stem is made up of little tubes.
Plants And Water
We need water to live and so do plants. Plants need water to make oxygen which is let out into the atmosphere and to make sugar. Do you know the name of that process?
Do plants use a lot of water? How about on a cold day? Albert has the answer.
Plants And Light
Plants need light to survive. Did you know plants grow towards light?
Try this experiment:
- Place a potted plant in a cardboard box.
- Now tear off one side off the end of the box.
- Place the holed side toward the light.
- After a few days the plant will lean towards the light.
Plants And Warmth
Plants like a certain amount of heat. Did you ever ask yourself why grass doesn’t grow in winter, it’s because grass tends to go into ‘hibernation’ when the weather is cold and there is very little sunlight.
Plants And Water
Photosynthesis is the process by which plants, some bacteria and some protistans use the energy from sunlight to produce sugar. The conversion of unusable sunlight energy into usable chemical energy is associated with the actions of the green pigment chlorophyll. Most of the time, the photosynthetic process uses water and releases the oxygen that we absolutely must have to stay alive. Oh yes, we need the food as well!
We can write the overall reaction of this process as: 6H2O + 6CO2 ----------> C6H12O6 + 6O2
Most of us don't speak ‘chemicalese’, so the above chemical equation translates as:
Six molecules of water plus six molecules of carbon dioxide produce one molecule of sugar plus six molecules of oxygen.
Chlorophyll
Chlorophyll is the molecule that absorbs sunlight and uses its energy to synthesise carbohydrates from CO2 and water. This process is known as photosynthesis and is the basis for sustaining the life processes of all plants. Since animals and humans obtain their food supply by eating plants, photosynthesis can be said to be the source of our life also.
Remember, as a member of the Science Bus Club you can ‘Ask Albert’ a question about any of the topics. So if you’re not already a member join today!!
