Frank Brothers Solutions for ICSE Class 9 Biology Chapter 11 Understanding Ecosystems

PAGE NO: 94

Question 1:
Answer:
Environment is the sum of all external conditions and influences that affect organisms. The environment may be divided into biotic i.e. living and abiotic i.e. non-living components.
It includes everything around us that helps or affects our daily lives. This ranges from the air we breathe to the plants and animals we see every day.
Teacher's Tip: Think of the environment as your "big home" that includes both living buddies and non-living things.
Exam Tip: Mention both biotic and abiotic components specifically to get full marks.

Question 2:
Answer:
Ecosystems are units consisting of living things and their specific habitats in the biosphere where living things interact with each other and their environment.
In an ecosystem, every organism has a specific role to play in maintaining balance. It is like a community where everyone depends on each other and their surroundings.
Teacher's Tip: An ecosystem is like a giant puzzle where every plant and animal is a necessary piece.
Exam Tip: Remember that an ecosystem must include the interaction between living things and their physical environment.

Question 3:
Answer:
Man made ecosystem is formed by major human modification or alteration in the natural environment. Examples of man-made ecosystems are aquarium, park, grassland, garden etc.
These are areas where humans decide which plants grow and which animals live there. Because they are created by us, they usually need regular maintenance to survive.
Teacher's Tip: If you have to water it or clean it yourself, it is probably a man-made ecosystem!
Exam Tip: Provide at least two examples like a garden or a cropland to support your answer.

Question 4:
Answer:
Two major types of ecosystems are natural ecosystem and artificial ecosystem.
Natural ecosystems like forests or oceans occur on their own in nature. Artificial ones are those created and managed by humans for specific purposes.
Teacher's Tip: Natural is made by Earth; Artificial is made by us!
Exam Tip: Ensure you use the term "artificial" or "man-made" interchangeably as they mean the same thing.

Question 5:
Answer:
Two features of forests are:
1. It includes a complex assemblage of different kinds of biotic and abiotic factors.
2. The temperature and rainfall conditions of a place determine the nature and characteristics of forests.
Forests are dense areas of vegetation that provide homes for countless species. The specific climate of the area determines whether the forest stays green all year or loses its leaves.
Teacher's Tip: Forests act as the "lungs" of our planet by cleaning the air we breathe.
Exam Tip: Number your points clearly as 1 and 2 to make them easy for the examiner to read.

Question 6:
Answer:
The trees in coniferous forests are found in single strands with no undergrowth. Plants predominantly found here include firs, pines, spruces and hemlock while the ground is covered with mosses, grasses, sedges and herbs that are adapted to cold.
These forests are usually found in cold regions where trees have needle-like leaves to survive the snow. The ground is often covered in soft moss instead of busy bushes.
Teacher's Tip: Coniferous trees are shaped like cones to help snow slide off easily!
Exam Tip: Mention specific tree names like "pine" or "fir" to show you have studied the details.

Question 7:
Answer:
Tropical rainforests are found in regions that experience high temperature, high humidity, heavy and well-distributed rainfall all year round. These regions lack seasonal changes and there is little difference between the length of days and nights. Tropical rainforests mainly occur inside the World’s equatorial regions. They are restricted to the small land area between the Tropic of Capricorn and the Tropic of Cancer.
These forests are very dense and stay green throughout the year due to constant rain. Because they are near the equator, they are some of the warmest and wettest places on Earth.
Teacher's Tip: Imagine a place where it is always summer and always raining - that is a tropical rainforest!
Exam Tip: Identify the geographical location "between the Tropics" to demonstrate geographical knowledge.

Question 8:
Answer:
Forest biome refers to the naturally occurring community of flora and fauna occupying the forest. Features of forest biomes are:
1. In tropical rainforest biomes, there is an amazing biodiversity of plants and animals. Trees are tall, with buttressed trunks and shallow roots, mostly evergreen, with large dark green leaves. Plants such as orchids, bromeliads, vines, lianas, ferns, mosses, and palms are present in tropical forests. Fauna include numerous birds, bats, amphibians, reptiles, small mammals, and a huge diversity of insects.
2. In deciduous rainforest biomes, many types of tall and short trees, shrubs, herbs, mosses and lichens are found occupying five different layers. Also a huge variety of fauna like panda, brown bear, hedgehog etc are found.
3. Not much biodiversity occurs in coniferous forest biomes. The trees here are found in single strands with no undergrowth. Plants predominantly found here include firs, pines, spruces and hemlock while the ground is covered with mosses, grasses, sedges and herbs that are adapted to cold. Fur bearing animals are found abundantly like brown bear, fox, mink, beavers, deer and large birds of prey like red tailed hawks. Many animals migrate or hibernate during the extremely cold winters.
Biomes are large areas characterized by specific plants and animals that have adapted to that climate. Each type of forest biome has unique features that help its residents survive in their specific environment.
Teacher's Tip: A biome is just a very large category of ecosystems with similar weather.
Exam Tip: Clearly distinguish between Tropical, Deciduous, and Coniferous biomes by focusing on their rainfall and temperature.

Question 9:
Answer:
Terrestrial ecosystem
These ecosystems are less dominant than aquatic ecosystems.
The organisms here are adapted to live on land.
The different kinds of terrestrial ecosystems are forest, grassland, deserts and tundra ecosystem.
Aquatic ecosystem
Aquatic ecosystems cover more than 70% of the earth’s surface.
The organisms here are adapted to live in water.
The different kinds of aquatic ecosystems are fresh water, marine water and brackish water ecosystem.
Terrestrial ecosystems are everything we see on land, while aquatic ecosystems are found in our oceans and rivers. Life on land requires breathing air, while life in water requires special adaptations like gills.
Teacher's Tip: "Terra" means earth or land, so terrestrial always refers to things on the ground!
Exam Tip: Mention that aquatic ecosystems are the most dominant type on our planet.

Question 10:
Answer:
(i) (d) all plants and animal species along with environment.
(ii) (c) an artificial ecosystem
(iii) (c) communities of organisms interacting with one another
(iv) (c) Tansley
(v) (c) 100-150 cm
(vi) (b) Decomposers
These objective questions cover the key terms and scientists who defined the study of ecosystems. Knowing names like Tansley and terms like decomposers is essential for a complete understanding.
Teacher's Tip: Match the letter option with the full phrase to be extra sure of your answer.
Exam Tip: Write the correct option letter AND the answer text for maximum clarity.