NCERT MOST IMPORTANT QUESTIONS CLASS – 11 | GEOGRAPHY | CHAPTER- 15 | LIFE ON EARTH | EDUGROWN |

In This Post we are  providing  CHAPTER 15 LIFE ON EARTH NCERT MOST IMPORTANT QUESTION for Class 11 GEOGRAPHY which will be beneficial for students. These solutions are updated according to 2021-22 syllabus. These MCQS  can be really helpful in the preparation of Board exams and will provide you with a brief knowledge of the chapter.

NCERT MOST IMPORTANT QUESTION ON LIFE ON EARTH

Question 1.
What is a bio in?
Answer:
Natural ecological groups of plants and animals extend over large areas. Each of these major terrestrial ecosystems or distinctive terrestrial areas with their group of plants and associated animals are recognized as biomes. A biome is, therefore, the largest terrestrial community of plants and associated animals in interaction with the environment.

Question 2.
What kind of animals live in tropical rain forests?
Answer:
The animals living in tropical rain forests include monkeys, snakes, ant-eaters, tropical birds, bats, large carnivorous animals, and a variety of fish in the rivers. Of all the species of insects known nearly 70 to S0% occur in the tropical rain forests.

Question 3.
What kind of flora and fauna characterize the deserts?
Answer:
Deserts are characterized by scanty flora and fauna. Desert plants include different kinds of acacias, cacti, euphorbias, and other succulents. Ants, locusts, wasps, scorpions, spiders, lizards, rattlesnakes, a large number of insect-eating birds such as swifts and swallows, seed-eating quails, doves, desert rats, rabbits, foxes, jackals, and various cats are the common desert animals.

Question 4.
What kind of plant and animal life is supported by tropical savanna?
Answer:
Savannas are characterized by coarse grass and scattered trees on the margins of the tropics where rainfall is seasonal. Wet seasons alternate with dry seasons. Plants and animals are drought-tolerant and do not show much diversity. This biome supports the greatest variety of hoofed herbivore species including the zebra, giraffe, elephant, and several kinds of antelopes. Kangaroos are found in the savannas of Australia.

Question 5.
What are the important features of the Mediterranean scrub forest as a biome?
Answer:
This biome is also known as Chapparal. This is marked by very limited winter rain followed by drought in the rest of the year. The temperature is moderate under the influence of the cool, moist air of the oceans. The biome is characterized by broad-leaved evergreen vegetation. It is made up of fire-resistant resinous plants and drought-adapted animals.

Question 6.
Write a note on deciduous forests.
Answer:
The deciduous forests are found in the temperate regions of north-central Europe, eastern Asia, and the eastern United States. The annual precipitation ranges between 75-150 cm. With the onset of autumn, most of the trees and shrubs become leafless. The vegetation comprises broad-leaved, hardwood trees such as oak, elm, beech, maple, and hickory. The fauna includes frogs, salamanders, turtles, snakes, lizards, squirrels, rabbits, deer, bears, raccoons, foxes, and songbirds.

Question 7.
“Food chains are not isolated linear chains of trophic levels.” Comment.
Answer:
In nature, the food relationship cannot be explained only in terms of a single food chain. A herbivore consumes many types of plants or plant products. Many kinds of animals, other than tiger, derive food from herbivorous animals. Ticks and mites, leeches, and blood-sucking insects are dependent on herbivores and even on carnivores. Thus, food chains are not isolated linear chains of trophic levels.

Depending upon the availability and choice of food, different organisms at each level have a food relationship with more than one organism at the lower levels. A rat, for example, feeds on various kinds of stem, roots, fruits, and grains. In turn, it is consumed by a snake which is eaten by a falcon. The snakes feed on both, frogs and rats. Then, a network of food chains exist, which is called a food web. The food web becomes more complicated when taste and preference, availability, and compulsion are involved.

Question 8.
Describe the functions of various biotic components.
Answer:
Various biotic components include producers, herbivores, carnivores, and decomposers. All organisms require energy for their life processes. Food supplies both energy and materials for the sustenance of life. Green plants produce carbohydrates by photosynthesis and also synthesize proteins and fats. The green plants, therefore, are called producers. The animals that consume this energy are called consumers.

The herbivores like cattle, deer, and goats derive their food or energy directly from plants and are called the first-order consumers. The carnivores like tiger and lion depend on herbivores for their food and energy and are therefore called the secondary or second-order consumers. The non-green organisms like fungi and some bacteria, which do not produce their own food, live on the dead and decaying plants or animals and are consumers of a special type called decomposers.

Question 9.
Describe the energy flow in the biosphere.
Answer:
Energy from the sun enters the living world through photosynthetic organisms and passes on from one organism to another in the form of food.

The organisms which trap solar energy and act as producers also use some energy for their own life processes. Only a portion of the energy trapped is taken by the primary consumers. Animals being more active than plants use much of the energy acquired before they are consumed by the next trophic level. At each stage of energy transfer, some amount of energy is lost from the food chain. The amount of energy transferred to the next higher level thus gradually decreases. The decomposition of dead organisms also releases chemical energy. Eventually, all this solar energy that entered the living system through the producers goes back into the non-living world, not as light but as heat.

Question 10.
Describe the carbon cycle in brief.
Answer:
Carbon is one of the basic elements of all living organisms. It forms the basic constituent of all organic compounds. The biosphere contains over half a million carbon compounds. The carbon cycle is mainly the conversion of carbon dioxide. This conversion is initiated by the fixation of carbon dioxide from the atmosphere through photosynthesis. Such conversion results in the production of carbohydrates, glucose that may be converted to other organic compounds such as starch, cellulose, etc. Here, some of the carbohydrates are utilized directly by the plant itself. During this process, more carbon dioxide is generated and is released through its leaves or roots during the day. The remaining unutilized carbohydrates become part of the plant tissue.

The plant tissues are either eaten by the herbivorous animals or get decomposed by micro-organisms. The herbivores convert some of the consumed carbohydrates into carbon dioxide for release into the air through respiration. The micro-organisms decompose the remaining carbohydrates after the animal dies. The carbohydrates that are decomposed get oxidized into carbon dioxide and are returned back to the atmosphere.