Class 9 Science - Chapter Diversity in Living Organisms NCERT Solutions | What are the differences between animals

How do poriferan animals differ from coelenterate animals?

Explain the basis for grouping organisms into five kingdoms.

Explain how animals in Vertebrata are classified into further subgroups.

Which organisms are called primitive and how are they different from the so-called advanced organisms?

How do gymnosperms and Angiosperms differ from each other?

What are the major divisions in the Plantae? What is the basis for these divisions?

Give three examples of the range of variations that you see in life-forms around you.

Which do you think is a more basic characteristic for classifying organisms?

(a) the place where they live.
(b) the kind of cells they are made of. Why?

How do annelid animals differ from arthropods?

What are the differences between amphibians and reptiles?

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?

What is sound and how is it produced?

The kinetic energy of an object of mass, m moving with a velocity of 5 m s^-1 is 25 J. What will be its kinetic energy when its velocity is doubled? What will be its kinetic energy when its velocity is increased three times?

Does the transfer of energy take place when you push a huge rock with all your might and fail to move it? Where is the energy you spend going?

A pair of bullocks exerts a force of 140 N on a plough. The field being ploughed is 15 m long. How much work is done in ploughing the length of the field?

The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes ¹⁶₈ X and ¹⁸₈ X in the sample?

Akhtar, Kiran and Rahul were riding in a motorcar that was moving with a high velocity on an expressway when an insect hit the windshield and got stuck on the windscreen. Akhtar and Kiran started pondering over the situation. Kiran suggested that the insect suffered a greater change in momentum as compared to the change in momentum of the motorcar (because the change in the velocity of the insect was much more than that of the motorcar). Akhtar said that since the motorcar was moving with a larger velocity, it exerted a larger force on the insect. And as a result the insect died. Rahul while putting an entirely new explanation said that both the motorcar and the insect experienced the same force and a change in their momentum. Comment on these suggestions

Why do organisms need water?

Write an expression for the work done when a force is acting on an object in the direction of its displacement.

Where is apical meristem found?

Conduct a survey in your neighbourhood to find out what the three most common diseases are. Suggest three steps that could be taken by your local authorities to bring down the incidence of these diseases.