Q1: What does the term ‘primitive’ refer to?
Ans: The term ‘primitive’ refers to early humans who were hunters and gatherers.
Q2: What is the goal of conservation strategy?
Ans: The goal of conservation strategy is to ensure that evolution continues allowing natural forces to maintain and evolve species.
Q3: Name the two sources providing food to man.
Ans: Plants and animals.
Q4: What are the different types of biodiversity?
Ans: There are three types of biodiversity: Genetic, Ecosystem, and Species diversity.
Q5: How much percentage of the known plants and animals of the world are at risk of extinction?
Ans: About 8% of wild plants and 22% of animals are at the risk of extinction.
Q6: Where would you find the greatest variety of hoofed herbivore species?
Ans: The greatest variety of hoofed herbivorous species is found in tropical savanna.
Q7: Which areas in the world consist of deciduous forests?
Ans: The deciduous forests are found in the temperate regions of north-central Europe, eastern Asia, and the eastern United States
Q8: What constitutes the dominant vegetation of Taiga?
Ans: Pine, fir, cedar, hemlock, and spruce constitute the dominant vegetation of Taiga.
Q9: Define ‘ecosystem’ with examples.
Ans: The biotic community, along with the physical environment forms an interacting system called the ecosystem. An ecosystem can be natural or artificial, temporary or permanent. A large grassland or a forest, a small 1 tract in a forest or a single log, an edge of a pond, a village, an aquarium, or a manned spaceship can all be regarded as an ecosystem.
Q10: How does the background of the habitat determine the distribution of animals?
Ans: The background of the habitat determines the distribution of animals by enabling them to camouflage against the color, general texture, and pattern. Desert animals like the lion and the camel are sand-colored. Most of the jellyfish, sea cucumbers are lassy. The chameleon changes its color according to its background.
Q11: What are different types of biodiversity?
Ans: Biodiversity exists at three levels, viz.,
Q12: Give examples of few sanctuaries of the country.
Ans: Some important sanctuaries of the countries are:
Q13: When and why did the mammals go extinct from the earth?
Ans: The prehistoric overkill by early humans in association with deterioration in climate has been recognized as the principal causes for the mammal extinction during the geological period of the Pleistocene, some 2 million years ago.
Q14: What is the conservation of biodiversity?
Ans: Conservation means ‘preservation’ of bio-diversity. The goal of conservation strategy is to ensure that evolution continues allowing natural forces to maintain and evolve species. It will maintain gene pools and retain genetic traits that may prove valuable in the future. Conservation also includes future efforts to protect species and to prevent rare ones from extinction.
Q15: What is meant by ‘Green Revolution’?
Ans: Green Revolution is related to agricultural development in India. It came in the 1970s when due to the planned efforts of the government of India, new varieties of seeds, fertilizers, insecticides, and pesticides were introduced to the farmers. This resulted in surplus agricultural production, particularly of foodgrains like wheat and rice.
Q16: Distinguish between exploitation and conservation of forest.
Ans: Both the acts are related to human usage of forests as a resource and are contradictory to each other. Exploitation means the usage of forests by human beings in an unfair and selfish manner for one’s own advantage or profit. On the contrary, conservation means the protection of forests. Here also man exploits the forest resources, but with a cautious effort, i.e. in such a manner that the evolution of species continues, preventing rare ones from extinction.
There are two levels of biodiversity. Genetic diversity comprises the genetic and related variations within the plant or animal species. It is concerned with their origin and evolution. On the other hand, species diversity is reflected by morphological and physiological features of the plant and animal species. It is related to the form and structure.
Q17: Write a short note on the man-made ecosystems.
Ans: Humans have changed the environment to a far greater .p extent than any other species. In some instances, the modification is so profound that we call them man-made or artificial ecosystems. These are of variable stability and duration. Villages and cities, orchards and plantations, gardens and parks with their plants and animals are familiar; examples of the man-made terrestrial ecosystem. Large dams and reservoirs, lakes, canals, small fishery, tanks, and aquarium are examples of the man-made aquatic ecosystem.
The most important man-made modifications in the biotic community came with the use of fire, cultivation of plants, and domestication of animals. All man-made ecosystems including agroecosystems are simpler and highly efficient. They lack the diversity of natural ecosystems. The consequence of diversity is stability. A simple system, on the other hand, is more vulnerable to sudden changes. A single crop agrosystem, for example, may be totally destroyed by drought, floods, diseases, pests, etc. A diversified system, on the other hand, has scope for many adjustments and substitutions.
Q18: Discuss the human developments that led to a negative impact on the biotic resources of the earth in the modern period.
Ans: The modem period is the age of industry and urbanization. The population is growing enabled with more lands being cleared of their forests, more soils being filled to grow crops, and more areas being used to erect homes, construct roads, build parking lots, and all the activities that channel resources toward urban locations. The loss of soil, movement of nutrients, and contamination of the environment with tonic materials are syrup to make of the excessive use of energy and unchecked outputs. Virtually every urban and industrial activity has a negative impact on water quality. Industrial and urban sewerage contain hazardous substances and cause eutrophication, diminishing the quality of the freshwater system. Human manipulation of nature has resulted in fragmented and incomplete systems. All these developments have a negative impact on the biotic resources of the earth.
Q19: Distinguish between a National Park and a Sanctuary.
Ans: National Parks: A national park is an area that is strictly reserved for the betterment of the wildlife and where activities like presenting, grazing, or cultivation are not permitted. In these parks, ‘ even the private ownership rights are not allowed. There are 66 national parks in India. Some important national parks are Kaziranga National Park (Assam), Sunderbans (West Bengal), Hazaribagh National Park (Jharkhand), Corbett National Park (Uttaranchal).
Sanctuary: Some important sanctuaries of the countries are:
Q20: What do you know about the boundaries of the ecosystem?
Ans: An ecosystem is an area in which the inputs and outputs can be studied across its boundaries. It is only for convenience that it is considered as a separate entity. Otherwise, ecosystems are not strictly isolated. Their boundaries are indistinct and overlapping. Some movement always occurs in their materials. This movement may be from an adjacent or distinct ecosystem. For instance, a pond may be separated from an adjoining grassland, but some birds may break the barrier and feed on the fish and crabs of the pond. The movement of energy and material can be achieved by biological climate or geological processes.
71 videos|245 docs|44 tests
|
|
Explore Courses for Humanities/Arts exam
|