Activity 15.2 Class 10 Science Our Environment

Activity 15.2 Class 10 Science Our Environment

Activity 15.2 asks us to discuss the incompatibility of fishes in the aquarium and observe the food chain of an aquatic ecosystem.

Answer and explanation: 

Some fishes eat other fishes, If we add such species together eventually there will be only predator fishes. To avoid this we should not mix a predatory fish with prey fish.

Some common predatory fishes are perch, muskie, pike, walleye and salmon.

how each of the above groups of organisms is dependent on each other?

In an aquatic ecosystem, all animals and plants remain in balance with each other. Small fishes eat phytoplankton and aquatic plants. By eating plants they check the overgrowth of the planktons and plants. Small fishes are not invincible, predatory fishes eat them and keep a balance on them. Large fishes eat small fishes and this process goes on.

All these constitute different trophic levels. With each successive trophic level energy transfer efficiency decreases. So, energy at a higher trophic level is low. This lesser energy at higher trophic level checks the uncontrolled proliferation of big predatory fishes.

Order of food chain in an aquatic ecosystem:

Aquatic plants<Small fishes<large fishes<larger fishes

Would you consider any one group of organisms to be of primary importance? Why or why not?

In an aquatic ecosystem, every trophic level is important for successive level. A slight change at any trophic level disturbs the ecosystem at a greater level. In all food chains, producers are the most important as only this trophic level utilise solar energy and provide food to other trophic levels. So, in a natural aquatic system aquatic plant are a must.

In the artificial aquatic ecosystem like an aquarium, the source of food is the packaged food pallets. Here the interaction of organisms with others is less.

Next: Debate and discussion on the presence of pesticides in food products: Activity 15.3.

See also: Aquarium components and its maintenance: Activity 15.2.: Activity 15.1 class 10 Science.