Question 1

Question 1:
What is the functional unit of the environment comprising of the living and non-living components called?

Accepted Answer

Answer:
The functional unit of the environment consisting of living and non-living components is called an ecosystem.

Question 2

Question 2:
Name two natural ecosystems and two artificial ecosystems.

Accepted Answer

Answer:
Two natural ecosystems are the pond ecosystem and the forest ecosystem. Two artificial ecosystems are the crop field ecosystem and the aquarium ecosystem.

Question 3

Question 3:
Which one of the following is not a terrestial ecosystem?
Forest, Grassland, Aquarium, Desert

Accepted Answer

Answer:
Among the given ecosystems, an aquarium is not a terrestrial ecosystem.

Question 4

Question 4:
Why are plants called producers?

Accepted Answer

Answer:
Plants are known as producers because they prepare their food themselves by the process of photosynthesis.

Question 5

Question 5:
What name has been given to those organisms which break down the complex organic compounds present in dead animals and plants?

Accepted Answer

Answer:
Organisms that break down the complex organic compounds present in dead animals and plants are called decomposers.

Question 6

Question 6:
What are planktons?

Accepted Answer

Answer:
The tiny herbivorous plants and animals present in water are known as plankton. Plankton are classified as phytoplankton (plants) and zooplankton (animals).

Question 7

Question 7:
State whether the following statements are true or false :
(a) In biology, human beings are called producers.
(b) Secondary consumers and tertiary consumers, both are carnivores.

Accepted Answer

Answer:
(a) False. Green plants are known as producers.
(b) True.

Question 8

Question 8:
Which category of organisms forms the starting point of a food chain?

Accepted Answer

Answer:
Producers (green plants) form the starting point of a food chain.

Question 9

Question 9:
Which of the following belong to the same trophic level?
Goat ; Spider ; Plants ; Hawk ; Rat

Accepted Answer

Answer:
Goats and rats belong to the same trophic level as they are both herbivorous animals.

Question 10

Question 10:
Which of the following belong to the same trophic level?
Tree ; Frog ; Snake ; Grass ; Lizard

Accepted Answer

Answer:
Trees and grass belong to the same trophic level as they are both producers.

Question 11

Question 11:
Write an aquatic food chain.

Accepted Answer

Answer:
A food chain that operates in a water body, such as a pond, a lake or an ocean, is known as an aquatic food chain.

Question 12

Question 12:
Name the organisms belonging to the second and the fourth trophic levels in the food chain comprising the following :
Frogs, Plants, Snakes, Hawk, Insects

Accepted Answer

Answer:
The second trophic level consists of insects, and the fourth trophic level consists of snakes.

Question 13

Question 13:
What are the various steps of food chain called?

Accepted Answer

Answer:
The various steps of a food chain are called trophic levels.

Question 14

Question 14:
Construct a food chain comprising the following :
Snakes, Hawk, Rats, Plants

Accepted Answer

Answer:
Plants → Rats → Snakes → Hawks

Question 15

Question 15:
Arrange the following in a food chain :
Fish, Algae, Small animals, Big Fish

Accepted Answer

Answer:
Algae → Small animals → Fish  → Big fish

Question 16

Question 16:
Which organisms belong to third and fourth trophic levels in the food chain comprising the following?
Rats, Plants, Hawk, Snakes

Accepted Answer

Answer:
Snakes belong to the third trophic level and hawks belong to the fourth trophic level in the food chain.

Question 17

Question 17:
Which one term in the following includes the others?
air, flora, fauna, environment, water, sunlight, soil

Accepted Answer

Answer:
Environment is the term that includes the others, i.e., air, flora, fauna, water, sunlight and soil.

Question 18

Question 18:
A food chain represents a unidirectional flow of X. What is X?

Accepted Answer

Answer:
A food chain represents a unidirectional flow of energy. 
X is energy.

Question 19

Question 19:
Fill in the following blanks with suitable words :
(a) Decomposer organisms are..........in their action.
(b) In nature, all green plants are............ whereas animals are consumers.
(c) A series of organisms, each of which feeds on the next organism, the beginning of which is a green plant, is called a .............
(d) The science that deals with the inter-relationships of living things with one another and their environment is called...........
(e) Plastic is a ...............material whereas paper is a.............material.

Accepted Answer

Answer:
(a) Decomposer organisms are specific in their action.
(b) In nature, all green plants are producers, whereas animals are consumers.
(c) A series of organisms, each of which feeds on the next organism, the beginning of which is a green plant, is called a food chain.
(d) The science that deals with the inter-relationships of living things with one another and their environment is called ecology.
(e) Plastic is a non-biodegradable material, whereas paper is a biodegradable material.

Question 20

Question 20:
Explain the terms 'producer' and 'consumer'. Give two examples of producers and two of consumers.

Accepted Answer

Answer:
Organisms that produce their own food from simple inorganic substances such as water and carbon dioxide are called producers. Examples are green plants and blue-green algae.
Organisms that consume the food prepared by producers are called consumers. Examples are cows and human beings.

Chapter 5 : Our Environment