Interdependence of Living Beings: Plants and Animals
Section I
A. Choose the correct option:
1. When animals die, they are converted back to
a. oxygen. [ ]
b. carbon dioxide. [ ]
c. sunlight. [ ]
d. nutrients. [✓]
2. Plants depend on animals for
a. nutrients. [ ]
b. dispersal of seed. [ ]
c. carbon dioxide. [ ]
d. all of these. [✓]
3. Non-living components of the environment include
a. air. [ ]
b. light. [ ]
c. soil. [ ]
d. all of these. [✓]
4. An example of a herbivore is
a. Goat. [✓]
b. Lion. [ ]
c. Cat. [ ]
d. Tiger. [ ]
5. An example of a scavenger is
a. Elephant. [ ]
b. Giraffe. [ ]
c. Vulture. [✓]
d. None of these. [ ]
B. Name the following:
a. The dependence of plants on animals, and animals on plants
= Interdependence.
b. The process of making food by plants
= Photosynthesis
c. Living things that can make their own food
= Producers.
d. Living things that can not make their own food, and depends an plants for food
= Consumers.
e. Bacteria and fungi that break down the nutrients present in decaying matter are called
= Decomposer.
C. Write T for true and F for false:
a. Plants do not depend on animals. [F]
b. Plants give shelter and protection to some animals. [T]
c. Plants, animals, and microorganisms form the living components. [T]
d. All animals are consumers. [T]
e. Animals that feed on both plants and animals are called carnivores. [F]
D. Give two examples of the following:
1. Scavengers : Vulture, Termite.
2. Consumers : Lion, Tiger.
3. Decomposers : Bacteria, Fungi.
4. Omnivores : Bears, Human beings.
5. Microorganisms : Bacteria, Fungi.
Section II
E. Short Answer Questions:
1. Why are plants and animals depended on each other? (Give the main reason)
= Plants and animals are dependent on each other for survival.
2. What happens when an animal dies?
= When animals die, they are converted back into nutrients(by small organisms called microorganisms) and become a part of the soil.
3. All living organisms can be divided in how many categories?(based on their role in the environment)
= All living organisms can be divided in four categories.
They are - i) Producers, ii) Consumers,
iii) Scavengers, iv) Decomposers.
4. What are producers? Why are they important?
= All living organisms that can produce their own food are called producers.
Producers are the main source of food and energy to other living organisms.
5. Define decomposition.
= The process of breaking down complex nutrients into simpler substances by decomposers is called decomposition.
F. Long answer questions:
1. What do you understand by interdependence of plants and animals?
= Plants and animals are dependent on each other for survival. Plants provide animals with food, shelter, and protection. Similarly, the animals help plants in dispersal of seeds, and also provide the nutrients needed by them for making food.
2. What are consumers? How many consumers are there?
= All living organisms that cannot prepare their own food, and depend on plants or other living organisms for food are called consumers. All animals are consumers.
Consumers can be of the following types:
Animals that feed only on plants - Such plant eating animals are called herbivores. Cow, goat, sheep, elephant, and giraffe are examples of herbivores.
Animals that feed on animals - Such as flesh eating animals are called carnivores. Some carnivores feed on herbivores, whereas some feed on other carnivores. Lion, tiger, crocodile, fox, hawk, and snake are some examples of carnivores.
Animals that feed on both plants and animals - Such animals are called omnivores. Bears and human beings are examples of omnivores.
3. Describe food chain with suitable examples.
= Grass is eaten by grasshopper. The grasshopper is, then eaten by a frog. The frog is, again eaten by a snake and the snake is, finally eaten by a hawk. This forms a chain that links plants and different animals for food. Thus, a chain that shows how plants are eaten by animals who are then eaten by other animals is called a food chain. A food chain always begins with plants.
4. How is imbalance in nature caused?
= Primarily, imbalance in nature can be caused due to natural causes and man-made causes. Let us learn about them.
(a) Natural Causes :
i) Floods : Due to heavy rainfall, large amount of water sometimes accumulates in an area. This condition is called flood. This may kill a large number of plants and animals present there, thus causing imbalance in nature.
ii) Drought : During summer season, when rainfall does not occur for a long time, water bodies like river and lakes dry up. This condition is called drought. Large number of plants and animals die due to shortage of water.
iii) Forest fire : Sometimes lighting can cause fire in the forest that wipes out animals and plants in large numbers. This causes imbalance in nature.
(b) Man-made causes :
i) Lanes cleaning : It is the practice of cutting down trees and removing vegetation from a forest area for farming and other human activities. Land cleaning causes death of several kinds of plants and animals. It also leads to decrease in rainfall. It may also cause increase in the amount of carbon dioxide in the atmosphere.
ii) Hunting : It is the practice of killing or capturing animals for food, sport, or for products such as horns, leather, ivory and fur. Excessive and illegal hunting may result in death of animals of different kinds. For example, the number of rhinoceros that are killed for their horns is so large that very few of them are left in the world.
iii) Pollution : It is mostly caused by human activities such as throwing wastes in large amounts on lands and in water, and release of excessive smoke and poisonous gases from factories and industries. Pollution causes land and water to become poisonous for living organisms. This may cause several animals and plants to die.
iv) Forest fire : It is a practice of burning down parts of forests to clear it for farming or for making human settlements. Forest fires may also be caused by lighting strikes and other natural causes as already discussed before. Uncontrolled forest fires can kill all living organisms present in the forest.