Test: Class 7 Geography NCERT Based - 1 - UPSC MCQ

• The environment is our basic life support system. It provides the air we breathe, the food we eat, the water we drink and the land where we live. Human beings make cars, mills, factories and manufacture containers.

• They are responsible for deforestation and degradation. They have modified the natural environment to a great extent.

• An earthquake is measured with a machine that is called a seismograph.

• The magnitude of the earthquake is measured on the Richter scale. On the Richter scale, an earthquake of 2.0 or less can be felt only a little. An earthquake over 5.0 can cause damage from things falling.

• A 6.0 or higher magnitude is considered very strong and 7.0 is classified as a major earthquake.

• The amount of insolation decreases from the equator towards the poles. Therefore temperature decreases in the same manner.

• It is the major reason why the poles are covered with snow all the time. An equator is the hottest place on the earth.

• Temperature in cities is much higher than the villages because the concrete and metals in buildings and the asphalt of roads get heated up during the day.

• This heat is released during the night. Also, the crowded high rise buildings of the cities trap the warm air and thus raise the temperature of the cities.

These four subsystems are called "spheres." Specifically, they are the "lithosphere" (land), "hydrosphere" (water), "biosphere" (living things), and "atmosphere" (air).

• As we go up the layers of the atmosphere, the pressure falls rapidly. The air pressure is the highest at sea level and decreases with height.

• Horizontally the distribution of air pressure is influenced by the temperature of the air at a given place The air always moves from high-pressure areas to low-pressure areas.

Key Points

• As the river approaches the sea, the water speed decreases, and it begins to break up into several streams called distributaries. The rivers become so slow it begins to deposit its load.

• The collection of sediments of all the distributaries at the mouth forms a delta of the river. Each distributary forms its own mouth.

• A distributary is a stream that breaks down from a running river and does not join it back. This usually happens, when a river is about to reach a sea or an ocean and is losing its speed as a result of the same. Hoogli river is a distributary of Ganges river.

Hence, the correct option is 'C'.

• When water evaporates from land and different water bodies, it becomes water vapour. So the quantity of water in the atmosphere is known as humidity. When the air is full of water vapour, it is called a humid day. The water vapour condenses causing formation of water droplets. Clouds are just masses of such water droplets.

• When air is heated, it expands, becomes lighter and goes up. Cold air is denser and heavy. That is why it tends to sink. When hot air rises, cold air from the surrounding area rushes there to fill in the gap. That is how air circulation takes place.

• Our earth is like a terrarium. It is an artificial enclosure for keeping small house plants.

• The sealed enclosure combined with the heat entering the terrarium allows for the creation of a small scale water cycle. Therefore the same water that existed centuries ago still exists today.

• The earth movements are divided based on the forces which cause them. The forces which act on the interior of the earth are called Endogenic Forces and the forces which work on the surface of the earth are called Exogenic Forces.

• Endogenic forces sometimes produce sudden movement and at the other time, slow movements. Gravitational force acts on the centre of the earth.

1. Stratosphere : Ozone layer and flying aeroplanes 2. Thermosphere : Ionosphere 3. Troposphere : Air we breath 4. Mesosphere : Meteorites 5. Exosphere : Light gases

• When the lithospheric plates move, the surface of earth vibrates. These vibrations can travel all around the earth and are called earthquakes.

• These vibrations travel outwards from the epicentre as waves. Focus is the point where earthquakes occur, and it is also the origin of seismic energy.

Tropical Grasslands are

1. East Africa: Savanna

2. Brasil: Campos

3. Venezuela: Llanos

Temperate Grasslands are

1. Argentina: Pampas

2. North America: Prairies

3. South Africa: Veld

4. Central Asia: Steppe

5. Australia: Down

• As it rains heavily in the Amazon region, thick forests grow.

• The forests are in fact so thick that the dense roof created by leaves and branches does not allow the sunlight to reach the ground. Therefore the ground remains dark and damp. This is why only shed tolerant vegetation may grow here.

• The Amazon basin is highly rich in the variety of life found here.

• Animals: Monkey Sloth Ant-eating Tapirs Reptiles Crocodiles Snakes Python Anaconda Boa constrictor

• Birds : Toucans Bird of paradise Hummingbird Besides, the basin is home to thousands of species of insects and fishes. The flesh-eating Piranha fish is also found in the river

Following animals are found in the Tundra regions: 1. Seal 2. Walruses 3. Muskoxen 4. Arctic -owl 5. Polar bear 6. Snow fox Deer are found in the tropical grasslands.