Predators cannot perform

1. conduit for energy transfer
2. control prey species
3. make ecosystem stable
4. Allow the herbivore to be full of energy fixed by autotrophs.

Why does the exotic species become invasive and start spreading fast?

1. It gets better nutrition there.
2. Because of lack of competition from other exotic plants
3. Because of lack of natural predator
4. Because of successful establishment of food web.

The prickly pear cactus introduced in Australia in 1920s got famous because of lack of which population interaction?

1. Competition
2. Predation
3. Parasitism
4. Amensalism

The invasiveness of prickly pear cactus in Australia was controlled by introducing a predator from its natural habitat and this predator was

1. A ladybird
2. A moth
3. A wasp
4. A desert fly

Among the rocky Intertidal communities of American Pacific coast, the starfish Pisaster is an important

1. Prey
2. Predator
3. Parasite
4. Competitor

If in a hypothetical case, you remove a predator from an ecosystem and as a result few prey species get extinct. What does it show

1. Interspecific competition
2. Intraspecific competition
3. Parasitism
4. Commensalism

When predator keeps on eating the prey, then in the end there should be no more prey to be eaten by predator. But this situation is not observed in the case of predation in nature. Because

1. Predators are prudent enough
2. Prey has developed defense mechanism not to allow predators to overexploit them
3. Plants have developed behavioural and chemical defenses.
4. Both A and B

Monarch Butterfly

1. Biochemical defense mechanism
2. Acquires it during it's caterpillar stage by feeding on poisonous weed
3. Highly distasteful to predator Zebra
4. Both A and B

How many insects are phytophagous? And such interaction is called as

1. 30%, parasitism
2. 25% predation
3. 33% commensalism
4. 40% amansalism

Acacia and Cactus show which kind of defences?

1. Biochemical
2. Biomolecular
3. Morphological
4. Behavioural