Refraction of Refraction — Science STD 10 — Question

There are three plants A, B and C. The flowers of plant A open their petals in bright light during the day but close them when it gets dark at night. On the other hand, the flowers of plant B open their petals at night but close them during the day when there is bright light. The leaves of plant C fold up and droop when touched with fingers or any other solid object.

1. Name the phenomenon shown by the flowers of (i) plant A, and (ii) plant B.
2. Name one flower each which behaves like the flower of (i) plant A, and (ii) plant B.
3. Name the phenomenon exhibited by the leaves of plant C.
4. Name a plant whose leaves behave like those of plant C.
5. Which plant/ plants exhibit the phenomenon based on growth movements?

State and explain the reaction, if any, of the following metals with a solution of copper sulphate:

1. Gold.
2. Copper.
3. Zinc.
4. Mercury.

Some symbols are given below. Explain those symbols. Which disasters may occur if those symbols are ignored?

Sketch, labell and classify: Jellyfish

Write short notes: Homologous series.

The stem of a fruit tree X fixed in soil is cut in a slanting way. The upper part of stem of another fruit tree Y of different variety of same species is also cut in a slanting way. The cut stem of tree Y, without roots but having some leaves, is placed over the rooted cut stem of tree X in such a way that their cut surfaces fit together properly. While joining the two cut stems, care is taken to make sure that the layer Z of one cut stem is in contact with layer Z of the other cut stem. The joint of cut stem is The stem of a fruit tree X fixed in soil is cut in a slanting way. The upper part of stem of another fruit bound tightly with a piece of cloth and covered properly with polythene. Soon the cut heals and the two stems grow together and become one fruit tree producing leaves, flowers and fruits.

1. What is the name of this method of producing plants or trees?
2. What name is given to the cut stem of tree X having roots?
3. What name is given to the cut stem of tree Y which has no roots but has some leaves?
4. Name the layer Z.
5. Why should the layer Z of one cut stem be in contact with the layer Z of the other cut stem?
6. Name any four fruit trees which are usually bred by this technique.
7. State any one advantage of producing fruit trees by this technique.

Write short notes on: Leaching method

Observe the given diagram and answer the questions :

i. Name the process shown in the figure.
II. Name the colour that deviates the most.
iii. Name the colour that deviates the least.
iv. Name any one phenomenon in the nature which is based on the above process.
v. Define 'spectrum'.

Write short note: Pre-disaster management.