Exploring IB Biology: Concepts in Ecology

What is a fundamental niche?

• The actual space that an organism occupies in an ecosystem.

• The potential role and area an organism could occupy without any competition.

• The role an organism plays in its community, including its habitat and its interactions with other organisms.

• The physical adaptations an organism has to survive in its environment.

Which of the following best describes a symbiotic relationship?

• A relationship where both organisms compete for the same resources.

• A relationship where one organism benefits and the other is unaffected.

• A relationship where two or more species live together and interact closely.

• A relationship where one species preys on the other.

What is competitive exclusion?

• The process by which two species work together to share resources.

• The principle stating that two species competing for the same resources cannot coexist.

• The exclusion of a species from a habitat due to human activities.

• The ability of a species to exclude other species from its niche through better adaptation.

What is a keystone species?

• A species that is the most abundant in an ecosystem.

• A species that has an unusually large effect on its ecosystem relative to its abundance.

• A species that is at the top of the food chain.

• A species that can survive in a wide range of environmental conditions.

What is a mesocosm?

• A large biome found in a natural setting.

• A small-scale experimental tool that replicates the natural environment under controlled conditions.

• A computer simulation of an ecosystem.

• A large aquarium used for studying marine organisms.

Which of the following is NOT a type of symbiotic relationship?

• Mutualism

• Commensalism

• Parasitism

• Neutralism

In the context of competitive exclusion, what would likely happen if two species with identical niches were placed in the same environment?

• They would merge into a single species.

• They would divide the resources equally.

• One species would outcompete the other, leading to the latter's decline or extinction.

• They would alter their niches to avoid competition.

How can a keystone species influence an ecosystem?

• By being the most numerous species in the ecosystem.

• By having no predators within the ecosystem.

• By controlling the population sizes of other species, thus maintaining the structure of the ecosystem.

• By being the primary producer in the food chain.

Which of the following best exemplifies a mutualistic symbiotic relationship?

• A tapeworm living in the intestine of a mammal.

• A bee pollinating a flower while collecting nectar.

• A lion eating a zebra.

• Barnacles attaching to a whale's skin without affecting the whale.

What role do mesocosms play in ecological studies?

• They provide a natural, uncontrolled environment for studying ecosystem dynamics.

• They are used to study the effects of large animals on ecosystems.

• They allow for the study of ecosystem processes and interactions under controlled conditions.

• They are theoretical models used to predict future changes in ecosystems.