P-2 Environmental management — Science STD 10 — Question

Write short notes: Environmental conservation.

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 in brief about progressive changes in animal classification.

The descriptions of five kinds of images are given below:

1. Diminished and virtual.
2. Enlarged and real.
3. Enlarged and erect.
4. Real and inverted.
5. Virtual and the same size.

Which one of these describes the image formed:

1. On the retina of the eye?
2. By a magnifying glass?
3. By a convex driving mirror on a car?
4. By a plane mirror?
5. on the screen of a slide projector?

Effective disaster management makes us well prepared for future.

The solid element A exhibits the property of catenation. It is also present in the form of a gas B in the air which is utilised by plants in photosynthesis. An allotrope C of this element is used in glass cutters.

1. What is element A?
2. What is the gas B?
3. Name the allotrope C.
4. State another use of allotrope C (other than in glass cutters).
5. Name another allotrope of element A which exists as spherical molecules.
6. Name a yet another allotrope of element A which conduct electricity.

Write down structural formulae of the first four members of the various homologous series formed by making use of the functional groups.

(a) Draw a neat labelled diagram of human eye.
(b) What is the minimum distance of distinct vision for a normal human eye ?
(c) Name the capacity of the eye lens to change its focal length as per need.
(d) Name the defect of eye vision in which the focussing power of eye lens decreases with age.

Sketch, labell and classify: Planaria