Differentiate between parenchyma, collenchyma and sclerenchyma on the basis of their cell wall.
Parenchyma: The cells have slight cell dividers composed of cellulose.
Collenchyma: The cells have cell dividers thickened at the comers because of the gelatin statement.
Sclerenchyma: Their dividers are thickened because of lignin testimony.
Diagrammatically show the difference between the three types of muscle fibres.
What does a neuron look like?
Draw a labelled diagram of a neuron.
Complete the table:
Give three features of cardiac muscles.
Where is apical meristem found?
What are the functions of the stomata?
How many types of elements together make up the xylem tissue? Name them.
What is a tissue?
Name the following.
(a) Tissue that forms the inner lining of our mouth.
(b) Tissue that connects muscle to bone in humans.
(c) Tissue that transports food in plants.
(d) Tissue that stores fat in our body.
(e) Connective tissue with a fluid matrix.
(f) Tissue present in the brain.
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?
Two children are at opposite ends of an aluminium rod. One strikes the end of the rod with a stone. Find the ratio of times taken by the sound wave in air and in aluminium to reach the second child.
Differentiate between homogeneous and heterogeneous mixtures with examples.
If Z = 3, what would be the valency of the element? Also, name the element.
What does the odometer of an automobile measure?
Gravitational force acts on all objects in proportion to their masses. Why then, a heavy object does not fall faster than a light object?
What is the quantity which is measured by the area occupied below the velocity-time graph?
What is the primary characteristic on which the first division of organisms is made?
A train is travelling at a speed of 90 km h-1. Brakes are applied so as to produce a uniform acceleration of – 0.5 m s-2. Find how far the train will go before it is brought to rest.
During an experiment, a signal from a spaceship reached the ground station in five minutes. What was the distance of the spaceship from the ground station? The signal travels at the speed of light, that is, 3 × 108 m s-1.
A diver is able to cut through water in a swimming pool. Which property of matter does this observation show?