Ace Your Ecology Practice Test

An ecosystem includes both biotic (living) and abiotic (non-living) components that interact in a shared environment. This comprehensive interaction distinguishes an ecosystem from a simple biological community.

Abiotic factors are the non-living elements in an environment, such as temperature, water, and sunlight. Temperature, for example, significantly influences the functioning and distribution of organisms.

Photosynthesis is the process in which plants capture sunlight and convert it into chemical energy, storing it as sugars. This process is fundamental to most life on Earth as it provides the energy foundation for food chains.

Producers are organisms, typically plants and algae, that create their own food through photosynthesis. They form the base of the food chain by providing energy for all other organisms.

A habitat is the natural environment where an organism lives and thrives. It provides the essential resources and conditions required for the organism's survival and reproduction.

A food web illustrates the complex network of feeding relationships within an ecosystem. It demonstrates that organisms often have multiple feeding connections rather than a single, linear chain.

Ecological succession is the orderly and predictable sequence of changes in an ecosystem after a disturbance. It results in the gradual transformation of the ecosystem until a stable climax community is achieved.

Carrying capacity is influenced by multiple interacting factors such as food, water, space, and the effects of competition and predation. All these factors together determine the maximum population size an ecosystem can support.

Decomposers break down dead organic material, returning essential nutrients to the soil and water. This recycling process is critical in sustaining the nutrient cycles that support plant growth and overall ecosystem health.

Biodiversity improves an ecosystem's ability to recover from environmental disturbances because a wide variety of species can compensate for each other. This redundancy ensures that if one species declines, others can help maintain ecological balance.

Sunlight is the principal energy source that drives the process of photosynthesis in plants. Without sunlight, the energy flow through terrestrial food chains would be disrupted, affecting nearly all life forms.

An ecological niche refers to the role an organism plays in its environment, including its interactions, resource use, and contribution to energy flow. It goes beyond mere habitat, defining how a species makes a living within its ecosystem.

Invasive species often disrupt native ecosystems by competing for resources and sometimes preying on native organisms. This competition can reduce native biodiversity and alter the balance of the ecosystem.

Nutrient cycling is the process by which essential elements, such as nitrogen and phosphorus, are recycled through an ecosystem. This continuous movement is vital for maintaining soil fertility and supporting plant growth.

Deforestation removes critical habitat for many species, leading to a decline in biodiversity. The loss of trees and vegetation can also disrupt local climate and soil conditions, undermining the ecosystem's stability.

A trophic cascade occurs when alterations at the top of the food chain cause a ripple effect throughout the ecosystem. This concept highlights the interconnectedness of species, where the loss or addition of a predator can significantly affect multiple lower trophic levels.

Climate change modifies regional climates by altering temperature and precipitation patterns, which can drive the geographical shifts of biomes. As these environmental conditions change, species distributions and ecosystem boundaries may also migrate accordingly.

The competitive exclusion principle posits that if two species compete for the exact same limited resource, one will eventually outcompete the other. This concept is fundamental in understanding how species diversify their niches to coexist within the same ecosystem.

An ecological footprint quantifies the extent of environmental impact caused by human consumption and waste production. This measure is significant for assessing sustainability and guiding efforts to reduce the human strain on natural resources.

Conservation biology focuses on safeguarding biodiversity through habitat restoration, genetic conservation, and sustainable management practices. These strategies are essential for mitigating the adverse effects of global environmental changes on ecosystems.