Lakhmir Singh Solutions - Biology - Class 10 solutions for Chapter 3 Our Environment

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

Name two natural ecosystems and two artificial ecosystems.

Why are plants called producers?

What are planktons?

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.

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

Which of the following belong to the same trophic level?

Goat; Spider; Plants; Hawk; Rat

Write an aquatic food chain.

Name the organisms belonging to the second and the fourth trophic levels in the food chain comprising the following:

Frogs, Plants, Snakes, Hawk, Insects

What are the various steps of the food chain called?

Construct a food chain comprising the following:

Snakes, Hawk, Rats, Plants

Arrange the following in a food chain:

Fish, Algae, Small animals, Big Fish

Which organisms belong to third and fourth trophic levels in the food chain comprising the following?

Rats, Plants, Hawk, Snakes

Which one term in the following includes the others?

Air, flora, fauna, environment, water, sunlight, soil

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

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.

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

(a) Define decomposers. Name one decomposer.

(b) What is the role of decomposers in the ecosystem?

Give an example of a four-step food chain operating in grassland. Name the secondary consumer in this food chain.

Consider the food chain :

Grass → Deer → Lion

What will happen if all the lions are removed from the above food chain?

The number of malaria patients in a village increased tremendously when a large number of frogs were exported from the village. What could be the cause of it?

Which of the following are biodegradable and which non-biodegradable?

Glass bottle, Paper, Ballpoint pen refill, Hay, DDT, Wheat, Cake, Wood, Polythene bag, Jute bag, Cotton cloth, Grass, Vegetable peels

Write down a food chain:

(a) in the sea

(b) which ends with humans

(c) with five links in it.

At which trophic level a person is feeding when he is eating:

(a) roasted chicken

(b) bread

(c) eggs

(d) apple

(e) fish

Construct (a) a long food chain, and (b) a short food chain, ending with a man.

(a) State one advantage of using jute bags over plastic bags for shopping.

(b) Write a common food chain of a pond ecosystem having four links.

We do not clean ponds or lakes but an aquarium needs to be cleaned periodically. Why?

What will be the consequence of the absence of decomposers in the ecosystem?

(a) What is meant by biodegradable waste materials? Give two examples of biodegradable wastes.

(b) Which of the following materials is non-biodegradable?

Aluminum wire, Tea leaves, Synthetic fiber, Wool

(a) What is meant by the 'environment'?

(b) What type of substances are the major pollutants of the environment? Name two such substances.

(c) Name the organisms whose uncontrolled activities are damaging the environment.

(d) Explain why it is better to use paper bags than plastic bags.

Which of the following constitutes a food chain?

(a) Grass, Wheat, and Mango

(b) Grass, Goat, and Human

(c) Goat, Cow, and Elephant

(d) Grass, Fish, and Goat

Which of the following represents a possible food chain found in a pond :

	Primary producers	Primary consumers	Secondary consumers
(a)	green algae	Fish	mosquito larvae
(b)	fish	green algae	mosquito larvae
(c)	mosquito larvae	Fish	green algae
(d)	green algae	mosquito larvae	fish

Which of the following are decomposers of dead organisms?

	Bacteria	Fungi	Viruses
(a)	No	Yes	Yes
(b)	Yes	No	Yes
(c)	Yes	Yes	No
(d)	Yes	Yes	Yes

Which of the following is an artificial ecosystem?

(a) pond

(b) crop field

(c) lake

(d) forest

In a food chain, the third trophic level is always occupied by:

(a) carnivores

(b) herbivores

(c) decomposers

(d) producers

Accumulation of non-biodegradable pesticides in the food the chain in an increasing amount at

each higher trophic level is known as:

(a) eutrophication

(b) pollution

(c) biomagnification

(d) accumulation

If a grasshopper is eaten by a frog, then the energy transfer will be from:

(a) producer to decomposer

(b) producer to primary consumer

(c) primary consumer to secondary consumer

(d) secondary consumer to tertiary consumer

The decomposers in an ecosystem :

(a) convert inorganic material to simpler forms

(b) convert organic material to inorganic forms

(c) convert inorganic material into organic compounds

(d) do not break down organic compounds

What will happen if deer is missing in the food chain given below?

Grass → Deer → Tiger

(a) The population of tigers increases

(b) the population of grass decreases

(c) Tigers will start eating grass

(d) The population of tigers decreases and the population of grass increases.

Organisms which synthesize carbohydrates from inorganic compounds by using radiant energy are called :

(a) decomposers

(b) producers

(c) herbivores

(d) carnivores

In the following groups of materials, which group/groups contain only non-biodegradable materials?

(i) wood, paper, leather

(ii) polythene, detergent, PVC

(iii) plastic, detergent, grass

(iv) plastic, bakelite, DDT

(a) (iii)

(b) (iv)

(c) (i) and (iii)

(d) (ii) and (iv)

Which of the following statement is incorrect?

(a) all green plants and blue-green algae are producers

(b) green plants get their food from readymade organic compounds

(c) producers prepare their own food from inorganic compounds

(d) plants convert solar energy into chemical energy

Which of the following is not a non-biodegradable material?

(a) nylon socks

(b) plastic school bag

(c) jute carry bag

(d) polyester clothes

The use of one of the following will pollute the environment. This one is :

(a) paper carry bags

(b) cotton cloth carry bags

(c) nylon cloth carry bags

(d) jute carry bags

One of the following is not a consumer. This one is:

(a) giraffe

(b) antelope

(c) algae

(d) alligator

One of the following helps in the recycling of materials in an ecosystem. This one is:

(a) autotrophs

(b) saprotrophs

(c) omnivores

(d) carnivores

In the food chain comprising of a snake, grass, insect, and frog, the secondary consumer is :

(a) insect

(b) snake

(c) frog

(d) grass

The Sahara Desert was formed over a period of time due to one of

the following uncontrolled activities of man :

(a) excessive cutting down of forest plants and trees

(b) excessive killing of large herbivores

(c) excessive killing of large carnivores

(d) excessive use of poisonous chemicals herbicides

Lakhmir singh solutions biology class 10 Solutions for Chapter 3 our environment