Class 9 Science - Chapter The Fundamental Unit of Life NCERT Solutions | If the organisation of a cell is destroy

Carry out the following osmosis experiment:

Take four peeled potato halves and scoos each one out to make potato cups. One of these potato cups should be made from a boiled potato. Put each potato cup in a trough containing water. Now,

(a) Keep cup A empty
(b) Put one teaspoon sugar in cup B
(c) Put one teaspoon salt in cup C
(d) Put one teaspoon sugar in the boiled potato cup D.

Keep these for two hours. Then observe the four potato cups and answer the following:

(i) Explain why water gathers in the hollowed portion of B and C.
(ii) Why is potato A necessary for this experiment?
(iii) Explain why water does not gather in the hollowed out portions of A and D.

How does an Amoeba obtain its food?

Fill in the gaps in the following table illustrating differences between prokaryotic and eukaryotic cells.

Why is the cell called the structural and functional unit of life?

Why are lysosomes known as suicide bags?

Where do the lipids and proteins constituting the cell membrane get synthesised?

How is a prokaryotic cell different from a eukaryotic cell?

Make a comparison and write down ways in which plant cells are different from animal cells.

How do substances like CO2 and water move in and out of the cell? Discuss.

Who discovered cells, and how?

Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?

State the universal law of gravitation.

Which of the following are matter?

Chair, air, love, smell, hate, almonds, thought, cold, cold-drink, smell of perfume.

A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (Fig. 11.3). Let us take it that the force acts on the object through the displacement. What is the work done in this case?

What is meant by a pure substance?

How does the sound produced by a vibrating object in a medium reach your ear?

In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium observations are in agreement with the law of conservation of mass.

sodium carbonate + ethanoic acid → sodium ethanoate + carbon dioxide + water

What are canal rays?

State any two conditions essential for good health.

How is our atmosphere different from the atmospheres on Venus and Mars?

Write down the formulae of
(i) sodium oxide
(ii) aluminium chloride
(iii) sodium suphide
(iv) magnesium hydroxide

An object experiences a net zero external unbalanced force. Is it possible for the object to be travelling with a non-zero velocity? If yes, state the conditions that must be placed on the magnitude and direction of the velocity. If no, provide a reason.

State any two conditions essential for being free of disease.

Using a horizontal force of 200 N, we intend to move a wooden cabinet across a floor at a constant velocity. What is the friction force that will be exerted on the cabinet?

Write the distribution of electrons in carbon and sodium atoms.

What are the methods of preventing or reducing soil erosion?

What are the limitations of Rutherford’s model of the atom?

Flash and thunder are produced simultaneously. But thunder is heard a few seconds after the flash is seen, why?

List the points of differences between homogeneous and heterogeneous mixtures.

Which postulate of Dalton’s atomic theory is the result of the law of conservation of mass?