[ Question Bank ] - 2022 — Science STD 10 — Question

Why does human being have an important place in the environment?

Explain the factors affecting the rate of chemical reaction with example.

There are four tiny organisms A, B, C and D. The organism A is a parasitic protozoan which causes a disease known as kala-azar. The organism B is a microscopic single-celled animal which causes malaria disease in human beings. The organism C is a unicellular animal which can change its body shape according to need, it has no fixed shape. The organism D is also a unicellular animal which is slipper-shaped having a large number of tiny hair all around its body.

1. Name the organisms A, B, C and D.
2. Name one characteristic body feature of organism A.
3. Name the insect which carries organism B and transmits it from one person to another.
4. What name is given to the asexual method of reproduction of (i) organism A, and (ii) organism B?
5. Where do organisms C and D live?

When a broken piece of the stem of a plant X is planted in the soil, a new plant grows from it in a week's time. The leaves of plant X also have many small entities Y in their margins which can fall to the ground alone or alongwith leaves and grow into new plants.

1. Name a plant which X could be.
2. What are the entities Y present on the leaves of X known as?
3. Name a plant other than X which can be reproduced from its leaves.
4. Name a common plant grown in many homes which can be propagated from its broken stems like plant X.
5. Name a kind of dormant organs present in dry stems of old grass plants lying in the fields which get activated and produce green grass plants after the rains.

'Save energy' is the need of the hour.

State whether an electric heater will consume more electrical energy or less electrical energy per second when the length of its heating element is reduced. Give reasons for your answer.

Write the function of the human eye and label parts of the figure given below.

What are the demerits of Mendeleev’s periodic table?

A cylindrical structure P in our body begins in continuation with medulla and extends downwards. It is enclosed in a bony cage Q and surrounded by membranes R. As many as x pairs of nerves arise from the structure P. The structure P is involved in the reflex actions of our body and conduction of nerve impulses to and from another organ S of our body with which it forms CNS.

1. Name the structure P.
2. Name (i) bony cage Q, and (ii) membranes R.
3. How much is x?
4. Name the organs S.
5. What are the reflexes involving structure P only known as?

What does the central nervous system in humans consist of? What is the job of the central nervous system?