Class 9 Science - Chapter Diversity in Living Organisms NCERT Solutions | How are the criteria for deciding divisi

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?

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

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

How do annelid animals differ from arthropods?

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?

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?

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

Why is it not possible to see an atom with naked eyes?

Under which of the following conditions are you most likely to fall sick?
(a) when you are taking examinations.
(b) when you have travelled by bus and train for two days.
(c) when your friend is suffering from measles.

Why?

Explain with examples (i) Atomic number, (ii) Mass number, (iii) Isotopes and iv) Isobars. Give any two uses of isotopes.

A baby is not able to tell her/his caretakers that she/he is sick. What would help us to find out
(a) that the baby is sick?
(b) what is the sickness?

Why is the plasma membrane called a selectively permeable membrane?

What is the work done by the force of gravity on a satellite moving round the earth? Justify your answer.

Calculate the formula unit masses of ZnO, Na₂O, K₂CO₃, given atomic masses of Zn=65 u, Na=23 u, K=39 U, C=12 u and O=16 u.

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

If the moon attracts the earth, why does the earth not move towards the moon?