What are the desirable characters of bee varieties suitable for honey production?
Bee varieties having the following desirable characters are suitable for honey production:
(i) They should yield high quantities of honey. The bee varieties reared should produce more honey.
(ii) They should not sting much. Bees reared should sting less so that they can reared easily and the honey can be obtained easily.
(iii) They should stay in the beehive for long durations.
(iv) They should breed very well.
How do you differentiate between capture fishing, mariculture and aquaculture?
Explain any one method of crop production which ensures high yield.
How do good animal husbandry practices benefit farmers?
How do plants get nutrients?
What is genetic manipulation? How is it useful in agricultural practices?
How are fish obtained?
What are the desirable agronomic characteristics for crop improvements?
Which method is commonly used for improving cattle breeds and why?
What factors may be responsible for losses of grains during storage?
How do biotic and abiotic factors affect crop production?
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?
Why do we classify organisms?
Write the distribution of electrons in carbon and sodium atoms.
A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m.
How are sol, solution and suspension different from each other?
Name the technique to separate
(i) butter from curd,
(ii) salt from sea-water,
(iii) camphor from salt.
What is the role of epidermis in plants?
How would you choose between two characteristics to be used for developing a hierarchy in classification?
Which of the following are chemical changes?
(a) Growth of a plant
(b) Rusting of iron
(c) Mixing of iron filings and sand
(d) Cooking of food
(e) Digestion of food
(f) Freezing of water
(g) Burning of a candle.
Cite an experiment to show that sound needs a material medium for its propagation.
What are the limitations of J.J. Thomson’s model of the atom?