Grade Six Science
Hello Boys and Girls!
It’s time once again for Science. We are very near to our special assessment. Do lots and lots of revision of all of your work. If there is any area of which you are not quite sure, now is the time to have your teacher help you clarify these issues. Read over all your notes, not just those you know well and like. This week we will answer questions as well as do some revision. This will help you to remember your work. Do well.
1. Explain what is
Pollination: …………………… . ………… and name two types:……….….. ………… .. Fertilisation: ………………… . …………… ...................................................................... ......................................................................
2.
3. Name three agents of pollination ………… . …………………… . …………….................
4.
Describe flowers that are pollinated by insects… .............. …… ..................... ……… …………………… . …………….................
Complete this table 5. Draw a seed and label three parts.
Let’s look again at a few things that we have already learnt and remind ourselves of them.
A. What is germination? Look at the following stages of germination. ◊ Primary leaves begin to unfold. The stem gets stronger. ◊ The tree leaves completely emerge and the cotyledons eventually dry up and fall off.
Stages of Germination
● Although all living things look different from each other, they all do seven different life processes.
● Animals and plants are called living organisms.
● Something is only alive if it does all seven
processes.
Remember “MRS NERG”.
(i) M– Move – even just a bit
Animals usually move their whole bodies, moving from one place to another.
Leaves turn towards the light. Leaves grow down into the soil.
(ii.) R – Reproduce – living things have offspring
Animals have babies.
New plants grow from seeds.(Can you think of any other way in which we can get new plants?)
S – Sensitive – responding to changes Living things notice changes in their surroundings and react to them.
Plants grow towards light. A dog smells food and runs towards it
N - Nutrition – taking in food
Food is used to provide energy.
Green plants make their own food using sunlight.
Animals eat plants and other animals.
E – Excrete – getting rid of waste
Waste substances have to be removed from the body.
Both plants and animals need to get rid of waste gas and water. (What else?)
R – Respire – living organisms are active (iii) ( iv.) (v) (vi.)
B. Characteristics of living things
Plants and animals use the oxygen in the air to turn food into energy.
(vii.) G – Grow – they get bigger
Seedlings grow into bigger plants.
Babies grow into adults.
C.
A plant won’t live forever so it has to make new plants. This is called reproduction. Flowers are necessary for reproduction. They have colour and smell to attract insects. They make pollen (male sex cells) which join to the eggs (female sex cells) . Part of the flower dies and what’s left becomes the new fruit with seeds.
-Seed Dispersal:
This involves the scattering of seeds. The fruits and seeds must be carried away from the parent plant to stop overcrowding. This is called seed dispersal.
● Wind: The fruits are light and feathery and
so get blown by the wind.
● Animals: The fruits are juicy or sticky and
so get eaten or carried on animal fur. ● Explosion: The fruit skin (pod) dries up and
splits open, and so shoots out seeds.
D.
Flowers
The reproductive organs are inside the flower. The stamens contain the pollen grains and the carpel contains the ova or eggs.
The stamen is made up of the anther and filament. The filament holds the anther up.
-Pollination:
Some flowers are pollinated by insects. Insects are attracted to the flowers by their scent and brightly coloured petals.
Some flowers are pollinated by the wind. Can you name other such agents of pollination? Name this kind of pollination.
Do you know what is self – pollination?
-Fertilisation:
Fertilisation takes place after pollination. After pollination the pollen grains and the eggs join. When the pollen grains and the eggs join a seed is formed.
-Fruit Formation:
The flower (petals, etc.) dies and leaves behind a fruit with seeds.
The ovary becomes the fruit and contains the seed (ova).
Name three ways in which to disperse a fruit with seeds.
Leaves
Draw a leaf and name its parts.
Leaves are necessary for nutrition (feeding). The green chlorophyll in the leaves uses sunlight to change carbon dioxide gas and water into food – this is called photosynthesis.
Leaves are so important for nutrition and for excretion.
Let’s look again at photosynthesis. This is the process in which plants make their own food in the presence of sunlight. Photo means light and synthesis means making something. Photosynthesis takes in green leaves. Chlorophyll in green leaves uses light to change carbon dioxide gas and water into food and oxygen.