Question 1: Define the term 'ecosystem' and explain its main components.

Answer: An ecosystem is a community of living organisms interacting with each other and their non-living environment in a specific area. Its main components include plants, animals, soil, water, and the climate.

Question 2: Describe the key features of a tropical rainforest ecosystem.

Answer: A tropical rainforest ecosystem is characterized by high temperatures and heavy rainfall throughout the year, dense vegetation with tall trees, a rich diversity of plant and animal species, and a layered structure including emergent, canopy, and understorey layers.

Question 3: Identify three adaptations that plants in a desert ecosystem might have to survive the dry conditions.

Answer: Plants in deserts may have deep root systems to access underground water, thick waxy coatings on leaves to reduce water loss, and small or no leaves to minimize evaporation.

Question 4: Explain how the climate influences the types of animals found in a tundra ecosystem.

Answer: The cold temperatures, short summers, and limited vegetation in the tundra limit the types of animals that can survive there. Animals are adapted to cold conditions, have thick fur, fat layers, and behaviors like migration to cope with the harsh climate.

Question 5: Compare the biodiversity levels of a coral reef and a desert ecosystem.

Answer: A coral reef has high biodiversity with many species of fish, corals, and other marine life, while a desert has lower biodiversity due to its harsh, dry conditions limiting the variety of plants and animals that can survive there.

Question 6: Draw a simple diagram to show the layers of a rainforest ecosystem. Label the emergent layer, canopy, and understorey.

Answer: A correct sketch would show three horizontal layers: the top layer with tall, emergent trees; the middle layer with a dense canopy of leaves; and the lower layer (understorey) with smaller plants and young trees.

Question 7: Explain why wetlands are important ecosystems for the environment.

Answer: Wetlands are important because they provide habitats for many species, act as natural water filters, help control flooding, and store carbon to reduce climate change effects.

Question 8: Describe how human activity can threaten the health of a grassland ecosystem.

Answer: Human activities like overgrazing, farming, urban development, and pollution can damage grasslands by degrading soil, reducing plant diversity, and disrupting the habitats of native animals.

Question 9: Sketch and label the main features of a river ecosystem, including the source, riverbank, and estuary.

Answer: A correct sketch would show a flowing river starting from the source (mountain or hill), flowing downstream with banks on either side, and ending in an estuary where freshwater mixes with seawater.

Question 10: What is the role of decomposers in an ecosystem? Provide an example.

Answer: Decomposers break down dead organic material, returning nutrients to the soil or water, which helps maintain the health of the ecosystem. An example is bacteria that decompose fallen leaves.