How do plants and animals help each other in the exchange of gases in the atmosphere?
Animals breaths out carbon dioxide. This carbon dioxide can be used by plants to prepare their food, this process is called photosynthesis which makes the balance on earth. Animals and plants by exchange of gases help each other to survive.
How will you prove that air supports burning?
List five activities that are possible due to the presence of air.
The layer of air around the earth is known as ___________.
How will you show that air is dissolved in water?
What is the composition of air?
Why does a lump of cotton wool shrink in water?
The component of air used by green plants to make their food, is ___________.
Which gas in the atmosphere is essential for respiration?
(a) Which kind of garbage is not converted into compost by the redworms?
(b) Have you seen any other organism besides redworms, in your pit? If yes, try to find out their names. Draw pictures of these.
Rearrange the boxes given below to make a sentence that helps us understand opaque objects.
To walk through a waterlogged area, you usually shorten the length of your dress by folding it. Can this change be reversed?
Do you find that all living beings need the same kind of food?
Name the major nutrients in our food.
Classify the following fibres as natural or synthetic:
nylon, wool, cotton, silk, polyester, jute
Name five objects which can be made from wood.
Why do we need to separate different components of a mixture? Give two examples.
Correct the following statements and rewrite them in your notebook.
(a) Stem absorbs water and minerals from the soil.
(b) Leaves hold the plant upright.
(c) Roots conduct water to the leaves.
(d) The number of petals and sepals in a flower is always equal.
(e) If the sepals of a flower are joined together, its petals are also joined together.
(f) If the petals of a flower are joined together, then the pistil is joined to the petal.
Fill in the blanks:
(a) Joints of the bones help in the ——————— of the body.
(b) A combination of bones and cartilages forms the _______ of the body.
(c) The bones at the elbow are joined by a ______________________ joint.
(d) The contraction of the _____________ pulls the bones during movement.
You are given an iron strip. How will you make it into a magnet?
Which of the following plants have you seen? of those that you have seen, which one have flowers?
Grass, maize, wheat, chilli, tomato, tulsi, pipal, shisham, banyan, mango, jamun, guava, pomegranate, papaya, banana, lemon, sugarcane, potato, groundnut
Lemonade is prepared by mixing lemon juice and sugar in water. You wish to add ice to cool it. Should you add ice to the lemonade before or after dissolving
sugar? In which case would it be possible to dissolve more sugar?
Is it possible to separate sugar mixed with wheat flour? If yes, how will you do it?
Write the similarities and differences between the motion of a bicycle and a ceiling fan that has been switched on.
When does a drought occur?
What is a habitat?
If a plant has leaves with reticulate venation, what kind of roots will it have?
Name two foods each rich in:
(a) Fats
(b) Starch
(c) Dietary fibre
(d) Protein
Give an example of a non-living thing, which shows any two characteristics of living things.