Science 5 Marks Questions

1. Ecological Balance: Forests and wildlife are essential to maintain ecological balance of an area.
2. Renewable Natural Resources: Forests are an important renewable natural resources.
3. Ecosystem: Forests are the homes for various species- a complete self sustaining ecosystem, their species content varieties in different parts of the world.
4. Economic Development: Forest contributes to the economic development of the country because they provide goods and services to the people and industry.
5. Environment Quality: The forest enhances the quality of environment by influencing the life supporting system.
6. Safeguard against Pollution: Forest check air pollution and soil erosion. Thus, they exercise safety and against pollution.
7. Soil Conservation: Forest save the hill-slopes from landslides.
8. Wind Erosion: In deserts, trees reduce wind erosion by checking wind velocity.
9. Check the Extension Balance: The forest checks strong gales and keeps the soil intact beneath the roots of trees and thus checks extension of desert.
10. Maintains Ecological Balance: The forest check pollution of air through increasing oxygen content of the air.
11. Attracts Rainfall: By causing condensation of water vapour in clouds, forests attract rains.
12. Control Floods: The floods are controlled because forests dry up rainwater like sponge. It makes soil more fertile and hydrated.
13. Connects to our Cultural and Civilization: Forests are linked with our cultural and civilization.
14. Supply of Raw Material: Forest supply wood, which is used as.

• Fuel.
• Raw material for various industries as pulp, paper, newsprint, board.
• Timber for furniture items.
• To be used in packing articles like fruits, tea etc.
• For preparing matches, sport goods etc.

Forests are very important resource. We should be careful and concerned about the issues related to forest due to following reasonss:

• If there are no forest, there would be more floods and more sol erosion.
• Forest affect the global to global environment in a great way. for example: reduced forest cover in a particular area leads to global warming Which affects the whole earth.
• Forests are th dwelling of many animals. Deforestation will endanger our life and enviroment.
• In the absence of trees and plants, the animals will not get food and shelter.
• Forests provid us large number of useful products including wood, and medicines. These products would not be availbale in the absence of trees and plants.

1. The sequence of living organisms in which one organism eats another is called a food chain.

2.  

3. Scientific attitude, obligation to maintain the ecosystem of nature.

For a sustainable forest eco system, there has to be variety of animals and plants in a forest. Forest is a system comprising various plants, animals and micro-organisms. The various components of the forest are interdependent on one another. In the forest, there is interaction between soil, water, air and living organisms. Different layers of vegetation provide food and shelter for animals, birds and insects. All animals, whether herbivores or carnivores, depend ultimately on plants for food. Organisms which feed on plants often get eaten by other organisms, and thus part of some food chain. Many food chains can be found in the forest. All food chains are linked. Some micro-organisms called decomposer, like mushroom (fungi), feed upon the dead plant and animal tissues and convert them into a dark coloured substance called humus. Humus enriches the soil with nutrition which helps in plants growth. The dead animals become food for vultures, crows, jackals and insects. By harbouring greater variety of plants, the forest provides greater opportunities for food and habitat for the herbivores. Larger number of herbivores means increased availability of food for a variety of carnivores. Not only is this, decaying heap of animal dropping a source of food to various insects or decomposers which ultimately enrich the soil with nutrition in the form of humus.

Various type of animals (herbivores, carnivores, omnivores) live in forests and contribute to food chain. Following activities show how animals help forest grow and regenerate.

• Animals help in dispersal of seeds from one part of the forest to other part.
• Animal's excreta and their dead bodies when decomposed into soil act as manure for the plants.
• Microorganisms convert dead plants and leaves into hum us which is rich in nutrients. Humus in soil provide necessary min

Forests harbour great variety of plants and animals. Plants provide food to herbivores. Larger number of herbivores means increased availability of food for a variety of carnivores. Wide variety of animals helps forest to regenerate. Decomposers and scavengers are cleaning agents. So, every entity in the forest plays a key and vital role making it a dynamic living entity, full of life and vitality.

1. If forest disappear, the amount of carbon dioxide in air will increase, resulting in the increase of earth’s temperature.
2. In absence of trees and plants the animals will not get food and shelter.
3. In the absence of trees, the soil will not hold water, which will cause floods.
4. Deforestation will endanger our life and environment.

Forests are called the green lungs. This is because plants in forests release oxygen through the process of photosynthesis and help in providing oxygen to animals for respiration. Plants consume carbon dioxide released by the animals. In this way, plants help in maintaining a balance of oxygen and carbon dioxide in atmosphere.

The conditions and issues we have to face when forests disappears are:

• Soil erosion: Trees in a forest hold soil with their roots. If trees are gone, soil will be washed away.
• Landslides: Without trees, land will be very unstable and easily down the slope.
• Water pollution: Without tree roots holding the soil in a forest, soil will run into the river.
• Temperature increase: The amount of carbon dioxide in air will increase, resulting in the increase of earth's temperature.
• Loss of biodiversity: Plants and animals will lose their food and shelter.
• Floods: Bald hills and mountains can no longer hold back sudden flows of water, which cause floods.
• Increase in carbon dioxide: Depletion of forests results in increase in carbon dioxide, which will cause global warming.

1. Scavenger.
2. Vulture.
3. Decomposers.
4. Fungi (mushroom).

The wide variety of animals helps the forest to regenerate and grow. In forest, plants produce food. All animals, whether herbivores or carnivores, depend ultimately on plants for food. Organisms which feed on plants often get eaten by other organisms, and so on. For example, grass is eaten by insects, which in turn, is taken by the frog. The frog is consumed by snakes.

This is said to form a food chain:

Grass → insects → frog → snake → eagle.

Decomposers play an important role in the forest. They feed upon the dead plant and animal tissues and convert them into a dark coloured substance called humus. For example Fungi grow on decaying fruits and vegetables and convert them into humus. By harbouring greater variety of plants, the forest provides good opportunities for food and habitat for the herbivores. Larger number of herbivores means increased availability of food for a variety of carnivores, the wide variety of animals helps the forest to regenerate and grow. Thus forest is the dynamic living entity that is the full of life and vitality.

The wide variety of animals helps the forest to regenerate and grow. In forest, plants produce food. All animals, whether herbivores or carnivores, depend ultimately on plants for food. Organisms which feed on plants often get eaten by other organisms, and so on. For example, grass is eaten by insects, which in turn, is taken by the frog. The frog is consumed by snakes.This is said to form a food chain:
Grass → insects → frog → snake → eagle. Many food chains can be found in the forest. All food chains are linked. If anyone food chain is disturbed, it affects other food chains. These food chains produce a lot of supplementary products which are vital for the plants growth. The micro-organisms which convert the dead plants and animals to humus are known as decomposers. Decomposers help in maintaining the supply of nutrients to the growing plants in the forest. Decaying heap of animal dropping is good source of nutrition for plants in the forest. The decaying animal dung also provides nutrients to the seedlings to grow. The animals also disperse the seeds of certain plants and help the forest to grow.