Nutrition in Animals — Science STD 7 — Question

Explain how the digestion of cellulose occurs in grass eating animals.

Explain the following.
(i) Copper and aluminium wires are usually employed for electricity transmission. Explain the reason.
(ii) Explain how does the resistance of a wire vary with its length?
(iii) The tungsten is used almost exclusively for filament of electric lamp. Comment.

Explain the three form of water that exists in nature.

Write how the following seeds are dispersed?
(I) Seeds with wings
(II) Small and light seeds
(iii) Seeds with spines/hooks

One day, a five years old boy, Chintoo was playing with his toys in his room. After few minutes, he saw a wristwatch on his study table, so after seeing it, he got crazy and so much eager to play with that watch. Then, for 2 to 3 min, he was trying to analyse it that whether its a toy or something else, then suddenly, he was just about to throw it but at the same his mother entered into the room and took the watch back immediately from his hand.
(i) State the benefits of a wristwatch.
(ii) Briefly mention the values showed by Chintoo's mother here.

A bus travels 40 km in 1 hour and 20 minutes, whereas the same distance is covered by a car in 60 minutes. What is the ratio of the speed of the car to the bus?

Explain two neutralisation reactions related to daily life situations.

Distinguish between the following. Blood and Plasma.