The Class 8 biology chapter 4- Ecosystem, deal with basics of how living and non-living organisms interact with each other in an ecosystem or a community. Solve the Selina questions and compare it with ICSE Selina Class 8 Biology Chapter 4- Ecosystem Solutions to find out how correct you are with your answers. These solutions from BYJU’S saves a lot of time and energy by providing all the necessary solutions for the question included in your ICSE syllabus.
Here is a brief of what you learn in this chapter.
A community made of both living organisms and non-living organisms such as air, water, minerals, soils etc. is known as an Ecosystem. There are two ways of interpreting an ecosystem.
- An ecosystem can be considered to be an interdependent collection of plants and animals.
- An ecosystem can also be viewed as a structured system or community having general rules to govern them.
The nutrient cycles and the energy flows are the two ways in which the biotic(living) and abiotic(non-living) organisms interact with each other.
The ecosystem does not include the interactions among organisms alone, instead, it deals with the cooperation of the organisms with its environment as well. Though the ecosystems can be of any size, each of these ecosystems has a specific or limited space.
Multiple Choice Questions:
1. Put a tick mark against the correct alternative in the following statements:
a. The term “ecosystem” is derived from the Greek word “Oikos” meaning.
1. Body weight
Answer: 3. House
b. Rat in any food chain would occupy the position of
1. Tertiary consumer
2. Secondary consumer
3. Primary consumer
Answer: 3. Primary consumer
C. Evergreen broad-leaved trees are characteristic of
1. Tropical rain forests
2. Temperate deciduous forests
3. Coniferous forests
4. All of the above types of forests.
Answer: 1. Tropical rain forests
Short Answer Type:
Mention if the following statements are true (T) or false (F).
(a) Snakes are primary consumers (T/F)
(b) Some humans are strictly primary consumers & some others are of other types of consumers also (T/F)
(c) No ecosystem can survive without light (T/F)
(d) Cattle go to ponds for drinking water, so they are a constituent of the pond ecosystem (T/F)
Match the items in Column I with as many items as possible in Column II.
Column I Column II
1. Deer (i) Autotroph
2. Parrot (ii) Ecosystem
3. Cobra (iii) Pond
4. Pine tree (iv) Deciduous forests
5. Grasshopper (v) Parasite
Column I Column II
1. Deer (iii) Pond
2. Parrot (iv) Deciduous forests, Autotroph, Producer
3. Cobra (vi) Carnivore
4. Pine tree (iv) Deciduous forests
Rewrite the following in their correct sequence in a food chain:
(a) Snake ———Grasshopper ———- Grass ——— Frog
(b) Grass ——— Tiger ——— Deer
(c) Snake ——— Peacock ——— Rat ——— Wheat
(a) Grass ——— Grasshopper ——— Frog ——— Snake
(b) Grass ——— Deer ——— Tiger
(c) Wheat ——— Rat ——— Snake right arrow Peacock
Long Answer Type:
Differentiate among primary, secondary and tertiary consumers. Give one example of each in a food chain.
Solution: Self-food producers are plants that produce food through photosynthesis i.e. these are autotrophs. There are plant-eating animals called herbivores as Rabbits, deer, pigeons, cows, buffaloes etc. and insects like grasshoppers, bees, butterflies and crickets also eat plants or plant products as fruits, flowers, pollen grains and plant juices. Such animals are called primary consumers.
Animals like tigers, lions, wolves, lizards, frogs eat the primary consumers. Birds vultures, kites, eagles eat the primary consumer, (i.e. These birds will eat the flesh of many birds like pigeons, sparrows.) These animals or birds are called secondary consumers. Animals like snakes are eaten by the peacocks, they eat the secondary consumers and are called tertiary consumers. Owls and eagles are top carnivores. So it is a quaternary consumer.
Define the term (a) flora and (b) fauna.
Flora: Flora is the plants occurring in a particular area i.e. vegetative growth forms flora. Flora deals with plants. Fauna: The animals occurring in an area from the fauna of that area. Fauna deals with animals.
Flora and fauna of an area are the plants and animals found in that area.
List any three members each of the flora and fauna of tropical rain forests
The tropical rain forest is on the western coast of India and in the north, east.
Flora: bamboos, ferns, shrubs (Evergreen trees).
Fauna: leopards, jungle cats, monkeys, snakes, flying squirrels, insects, snails, centipedes, millipedes.
Define the following terms and give two examples in each case.
(a) Symbiosis (b) Parasitism (c) Predation
(a) Symbiosis: It refers to relationships between organisms of different species that show on intimate association with each other. Relationships that provide at least one of the participating species with a nutritional advantage are known as symbiotic relationships.
Examples of Symbiosis Relationships are of Fungus and photosynthetic alga and Microbes and cattle.
(b) Parasitism: There is a type of symbiotic relationship between organisms of different species is called parasitism where one organism, the parasite, benefits at the expense of the other, the host. Examples of Parasitism are 4 tapeworms, flukes, the Plasmodium species and mosquitoes.
(c) Predation: A predator is any consumer that kills and eats another living organism in order to obtain energy. The organism being eaten is called prey. Examples are Lions, Deer, Wolves, and Eagles.