Question 1: Define what is meant by an 'ecosystem'. Include at least two key components in your answer.

Answer: An ecosystem is a community of living organisms interacting with each other and their physical environment in a specific area. Key components include biotic factors (plants, animals, microorganisms) and abiotic factors (climate, soil, water).

Question 2: Describe the main characteristics of a tropical rainforest ecosystem, including climate, vegetation, and animal life.

Answer: A tropical rainforest ecosystem has a hot, humid climate with high temperatures and heavy rainfall throughout the year. It features dense, layered vegetation with tall trees, a variety of plant species, and a diverse range of animals such as primates, birds, insects, and reptiles.

Question 3: Explain how the climate of a desert ecosystem influences the types of plants and animals that can survive there.

Answer: The arid climate with low rainfall and high temperatures limits water availability, so plants are adapted to conserve water (e.g., cacti, succulents). Animals are often nocturnal to avoid daytime heat and have adaptations for water conservation, such as specialized kidneys.

Question 4: Identify and explain two ways in which human activity can threaten rainforest ecosystems.

Answer: Deforestation for agriculture or logging destroys habitats and reduces biodiversity. Mining and infrastructure development can also lead to habitat fragmentation and pollution, further harming the ecosystem.

Question 5: Compare the roles of producers, consumers, and decomposers within an ecosystem. Provide examples for each.

Answer: Producers, such as plants and algae, create energy through photosynthesis. Consumers, like herbivores and carnivores, eat producers or other consumers to obtain energy. Decomposers, such as fungi and bacteria, break down dead organic material, returning nutrients to the soil.

Question 6: Sketch a simple diagram of a food chain in a grassland ecosystem, including at least four levels. Label each level clearly.

Answer: A correct sketch would show the sun providing energy to grass (producer), which is eaten by a herbivore (e.g., rabbit), which is then eaten by a carnivore (e.g., fox), and finally decomposers returning nutrients to the soil. Labels should clearly identify each level.

Question 7: Describe the process of succession in a primary ecosystem, such as a volcanic island. Include the stages involved.

Answer: Primary succession begins with the colonization of bare, lifeless land by pioneer species like lichens and mosses. Over time, soil develops, allowing grasses and shrubs to grow. Eventually, trees establish, creating a mature, stable ecosystem.

Question 8: Explain how climate change might impact a tundra ecosystem. Consider temperature, vegetation, and animal adaptations in your answer.

Answer: Rising temperatures due to climate change can lead to melting permafrost, altering the landscape. Vegetation may shift to shrublands or forests, and animals adapted to cold environments (e.g., polar bears) may struggle to survive or be forced to migrate.

Question 9: Draw a diagram of the water cycle as it occurs in a forest ecosystem. Indicate the processes involved, such as evaporation, condensation, and precipitation.

Answer: A correct diagram would include a body of water or moist soil with arrows showing evaporation rising into the air, condensation forming clouds, and precipitation falling back to the ground. Also include processes like transpiration from plants.