Respiration in Organisms — Science STD 7 — Question

Why is vegetative propagation a preferred method of asexual reproduction?

Setting of curd is regarded as a chemical change, explain why?

While learning to ride a bicycle, Boojho lost his balance and fell. He got bruises on his knees and it started bleeding. However, the bleeding stopped after some time.
(i) Why did the bleeding stop?
(ii) What would be the colour of the wounded area and why?
(iii) Which type of blood cells are responsible for clotting of blood?

Besides finding correct answers, what else is important in science?

How can we prevent rusting?

Priya observed that lime water turned milky on blowing through a straw. What did she conclude?

Observe the formation of shadows by a glass plate, an wooden piece and a tracing paper and record your result.

Differentiate between two modes of transfer of heat, i.e. convection and conduction.

Complete the following table:
Table: Hot and cold objects

Object	Cold/ Cool	Warm/ Hot
Ice cream	✓
Spoon in a tea cup
Fruit juice
Handle of a frying pan