The Fundamental Unit of Life — Science STD 9 — Question

Describe the various steps involved in the purification of water for city water supply.

When extremely small particles X derived from the another of a flower were suspended in a liquid Y and observed through a microscope, it was found that the particles X were moving throughout the liquid Y in a very zig zag way. It was also observed that warmer the liquid Y, faster the particles X moved in its surface.

1. What could particles X be?
2. What do you think liquid Y is?
3. What is the zig-zag movement of particles X?
4. What is causing the zig-zag movement of particles X?
5. Name the scientist who discovered this phenomenon.
6. What does this experiment tell us about the nature of liquid Y?

Write the formulae of the following compounds. Also name the elements present in them.

1. Water.
2. Ammonia.
3. Methane.
4. Sulphur dioxide.
5. Ethanol.

Name two types of animal feed and write their functions.

Describe structure and functions of Golgi apparatus.

Write down the characters of bee variety suitable for bee keeping.

Three different vibrating objects produce three types of sounds X, Y and Z. Sounds X and Y cannot be heard by a man having normal range of hearing but sound Z can be heard easily. The sound X is used in hospitals to break kidney stones of a patient into fine grains whioch then get flushed out with urine. The sound Y is similar to that which is produced during an earthquake before the main shock wave is generated.

1. What type of sounds are (i) X, (ii) Y, and (iii) Z?
2. Name one device which can produce sound like X.
3. Name one device in a science laboratory which can produce sound like Y.
4. Name one device in our homes which can produce sound like Z.
5. What is the frequency range of sounds like Z?

Draw and label a plant cell. Write the main function of:

1. Chloroplast.
2. Plasma membrane.
3. Cell wall.
4. Lysosomes.
5. Chromosomes.
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