CBSE Class 7 Science MCQs

Question: Name the gas which is used by white blood cells to kill the invading bacteria. a) Oxygen b) Carbon dioxide c) Nitrogen d) Chlorine Answer: Oxygen   Question: What is the percentage of oxygen in the inhaled air? a) 21% b) 16.4% c) 18% d) 20% Answer:…

Class 7 Science Winds Storms and Cyclones Notes

Winds, Storms and Cyclones   2.1 Introduction Moving air is called Wind. If the speed of wind is low, it is pleasant. If the speed is high, it becomes destructive.   2.2 Air Exerts Pressure Take a tin can with a lid. Fill it approximately half with water. Heat the can on a…

Class 7 Science Waste Water Story Notes

Waste Water Story Water Water is the most common liquid on earth. It is needed by all living things to survive. We use water for drinking, cleaning, bathing, washing clothes, etc. Even the plants cannot survive without water. Clean water that is fit for drinking is called…

Class 7 Science Transportation in Animals and Plants Notes

Transportation in Animals and Plants TRANSPORT OF MATERIALS All organisms have a way of transporting substances from one part of the body to another. Complex animals and plants have well developed transport system. It is responsible for the following:   • Supply of nutrients…

Class 7 Science Soil Notes

Soil   Soil is very important natural resource and a gift from mother earth. It is capable of supporting life on earth. Soil forms a very thin layer on the surface of the earth, ranging from few mm to 3 to 4 meters. It is in this layer of the soil that the nutrients are…

Class 7 Science Reproduction in Plants Notes

Reproduction in Plants   A characteristic feature of all living organisms is that they give birth to young ones of their own kind. What would happen if new generations of species were not produced from their parents? The earth would turn out to be barren place with no life.…

Class 7 Science Nutrition in Plants Notes

Nutrtion in Plants   All living organisms need energy to perform various life activities. They obtain this energy from the food they eat. This process of taking food and its utilization by the body is called nutrition. The various components of food are called nutrients. These…

Class 7 Science Nutrition in Animals Notes

Nutrition in Animals Animals are heterotrophs. They obtain food from green plants or animals that feed on plants.   Herbivorous Animals: They feed only on plants or plant parts. Examples. Cow, buffalo, goat, deer, rabbit, horse and elephant.   Carnivorous Animals: They feed…

Class 7 Science Motion and Time Notes

Motion and Time   3.1 Introduction   In our daily life, we see various objects in motion. The walking man, the running cars, the water flowing in lakes, flying aeroplanes etc. are all examples of objects in motion.   - A body is said to be in motion if it changes its position…

Class 7 Science Light Notes

Light   5.1 Introduction   Light is a source of energy which enables us to see the world surroundings us. Light itself is not visible. Without light, we can not even imagine life on earth.   5.2 Light travels along a straight line First try to see the lighted candle through…

Class 7 Science Heat Notes

Heat   1.1 Introduction   We wear woollen clothes during winters when it is cold outside. Woollen clothes keep us warm. We prefer to wear light coloured cotton clothes when it is hot. These give us a feeling of coolness. There are various objects in our surroundings which may…

Class 7 Science Forests Our Lifeline Notes

Forests: Our Lifeline   INTRODUCTION   About one-third of the world’s land surface is covered by forests. It is an eco-system (plants and animals) which is dominated by trees. Forest provide the most useful renewable resources. They prevent soil erosion, replenish oxygen in…

Class 7 Science Fibre to Fabric Notes

Fibre to Fabric   Animal Fibre — Wool and Silk   Wool: Wool comes from sheep, goat, yak and some other animals. These wool-yielding animals bear hair on their body. Hair trap a lot of air. Air is a poor conductor of heat. So, hair keeps these animals warm. Wool is derived from…