Biotic Interaction — Set 4

Correct Answer: C. Mutualism

The wasp pollinates the fig flowers while the fig provides a site for the wasp to lay eggs. This is an obligate mutualism where neither can complete their life cycle without the other. It is a classic textbook example of co-evolution.

Correct Answer: B. Mutualism

The correct answer is 'Mutualism'. The double plus sign indicates that both species involved in the interaction receive benefits. Examples include nitrogen fixation and the relationship between coral and algae. This interaction increases the survival chances for both organisms.

Correct Answer: B. Commensalism

Commensalism is a (+, 0) interaction where one organism gains while the other is neutral. Cattle egrets following grazing cattle to catch stirred-up insects is a standard example. The cattle are neither helped nor harmed by the presence of the birds.

Correct Answer: C. Predation

Predation is a (+, -) interaction where the predator kills the prey for food. It is a vital mechanism for energy flow in all natural food webs. Predators often possess specialized adaptations like claws or sharp teeth.

Correct Answer: C. Amensalism

Amensalism is a (-, 0) interaction where one species is harmed and the other is unaffected. Microbes secrete chemicals to reduce competition for resources in their environment. This phenomenon has been utilized by humans to create medical antibiotics.

Correct Answer: B. Intraspecific

Intraspecific competition occurs when members of the same population compete for identical resources. It is a major factor that determines the carrying capacity of a habitat. This interaction often leads to the survival of the most fit individuals.

Correct Answer: C. Parasitism

Parasitism is a (+, -) relationship where the parasite relies on the host for its survival. Unlike predation, the parasite generally does not kill the host immediately. This interaction can weaken the host and make it vulnerable to other threats.

Correct Answer: B. Mutualism

The correct answer is 'Mutualism'. Both organisms in a lichen benefit from their close physical association. The alga produces organic food while the fungus provides water and minerals. They function together as a single biological unit.

Correct Answer: B. Competition

Competition is harmful to both parties because they must share a limited resource. This leads to reduced growth, reproduction, and survival for both species. It is a key driver of natural selection and biodiversity.

Correct Answer: B. Facultative mutualism

Facultative mutualism, also known as proto-cooperation, is where species benefit but can live independently. The relationship between birds eating ticks off large mammals is a perfect example. It provides an advantage but is not mandatory for life.