Observe the food web and answer the questions given below -
7.1 The mussel can be described as
a) Producer
b) Primary consumer
c) Secondary consumer
d) decomposer
Answer
7.1 c) Secondary consumer
In the food web, if we observe the position of mussels with respect to other organisms, we will notice that algae is the primary producer , microscopic animals consume algae and are the primary consumers and mussels are at the next trophic level and are the secondary consumers .
7.2 Which trophic level is incorrectly defined?
a) Carnivores – secondary or tertiary consumers
b) Decomposers – microbial heterotrophs
c) Herbivores – primary consumers
d) Omnivores – molds, yeast and mushrooms
Answer
7.2 d) Omnivores
Omnivores consume both plant and animal matter .
Molds, yeasts and mushrooms are saprophytes that feed on dead and decaying matter.
7.3 The given figure best represents:
a) Grassland food chain
b) Parasitic food chain
c) Forest food chain
d) Aquatic food chain
Answer
7.3 a) Grassland food chain
This food chain consists of grass, grasshopper, frog and snake that are present in a grassland ecosystem
7.4 Why do all food chains start with plants?
a) Because plants are easily grown
b) Because plants are nutritious
c) Because plants can produce its own energy
d) Because plants do not require energy
Answer
7.4 c) Because plants can produce its own energy
Green plants are autotrophs . They make their own food which is consumed by higher organisms . Thus they can produce their own energy and all food chains start with green plants
7.5 In the food web, what two organisms are competing for food?
a) A and B c) A and C
b) D and F d) B and D
Answer
7.5 d) B and D
B and D are present at the same trophic level
They consume the same organisms and thus compete for food
