Environment and its interdependence

What is an Ecosystem ?

• Coral reefs

• Habitat

• metamorphosis

• Exosphere

Answer explanation

A coral reef is an ecosystem because it supports diverse marine life through complex interactions among species. Corals provide habitat and food for fish and other organisms. This biodiversity contributes to nutrient cycling, energy flow, and ecological balance, making coral reefs vital to marine environmental health.

What term describes the role an organism plays in its ecosystem?

• Habitat

• Niche

• Community

• Population

Answer explanation

A niche refers to the unique role and position an organism has in its ecosystem, including how it obtains its food, interacts with other organisms, and contributes to the energy flow and nutrient cycle.

Which of the following best describes a habitat?

• The role an organism plays in its ecosystem

• The type of food an organism eats

• The physical environment where an organism lives

• The interactions an organism has with other species

Which biogeochemical cycle involves the processes of photosynthesis and respiration?

• Nitrogen cycle
  

• Water cycle

• Carbon cycle

• Phosphorus cycle

Answer explanation

The biogeochemical cycle that involves the processes of photosynthesis and respiration is the Carbon cycle.

Which type of succession occurs in an area where there was previously no soil?

• Primary succession

• Secondary succession

• Climax succession

• Tertiary succession

Answer explanation

Primary succession occurs in lifeless areas where there was previously no soil, such as lava flows, newly formed sand dunes, or areas left by retreating glaciers. It begins with pioneer species like lichens and mosses that can colonize bare rock, gradually creating soil and enabling other, more complex plant and animal communities to establish.

Which of the following best describes a keystone species?

• A species that is the largest in its habitat

• A species that has a disproportionately large impact on its ecosystem

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

• A species that migrates frequently

Answer explanation

A keystone species is one that has a disproportionately large impact on its ecosystem relative to its abundance. These species play a critical role in maintaining the structure and balance of their environment. Their presence or absence significantly affects the diversity and population levels of other species within the ecosystem. For example, sea otters are keystone species because they control sea urchin populations, which in turn helps maintain kelp forest ecosystems.

What is the greenhouse effect?

• The cooling of the Earth's surface caused by greenhouse gases

• The trapping of heat by greenhouse gases in the Earth's atmosphere

• The reflection of sunlight back into space by greenhouse gases

• The formation of greenhouse gases from industrial processes

Which of the following gases is considered a greenhouse gas?

• Oxygen

• Nitrogen

• Carbon dioxide

• Ozone

Answer explanation

Greenhouse gases like carbon dioxide (CO2), methane (CH4), and others trap heat in the Earth's atmosphere, contributing to the greenhouse effect and climate change.

Prairie dogs are known for their significant ecological role in their habitats primarily because they:

• Prey on larger herbivores

• Construct complex underground burrow systems

• Contribute to soil erosion

• Disperse seeds of native plants

Answer explanation

Prairie dogs are herbivorous rodents that play a crucial role in their ecosystems by creating extensive underground burrow systems. These burrows provide shelter for a variety of other animals and help aerate and enrich the soil.

Which of the following is an example of a physical adaptation in animals for their environment?

• A. Hibernation during winter

• Migration patterns

• Camouflage coloring

• Social behavior

Answer explanation

Camouflage coloring is a physical adaptation that helps animals blend into their surroundings, providing them with protection from predators or enhancing their ability to ambush prey.