Acids, Bases and Salts — Science STD 7 — Question

Govind is a student. He set up an experiment as shown here.

He placed the lighted candle below the iron rod at position Q He used the same amount of wax to hold all the drawing pin at positions A, B, C, X, Y and Z on the rod. Arrange the drawing pin according to the time, they take to drop from the rod, from the last to the first.

Describe how ice stupas are designed in Ladakh to preserve water.

Give a brief description of the process of synthesis of food in green plants.

Explain with the help of a diagram, how does the magnetic effect of electric current help in the working of an electric bell.

In the figure of a flower given below, label the parts whose functions are given below and give their names.

(i) The part which contains pollen grains.
(ii) The part where the female gamete is formed.
(iii) The female reproductive part, where pollen grains germinate.
(iv) The colourful part of flower which attracts insects.

What would happen if forests disappear?

Draw a labelled diagram of the human excretory system.

What is photosynthesis?

State differences between laboratory thermometer and clinical thermometer.