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 producers (plants), consumers (animals), decomposers (fungi, bacteria), and the physical environment (soil, water, climate).

Question 2: Describe how the climate influences the types of plants and animals found in a tropical rainforest ecosystem.

Answer: A tropical rainforest has a hot, humid climate with high rainfall throughout the year. These conditions support lush, dense vegetation and a wide variety of animal species adapted to warm and moist environments. The consistent climate allows for continuous growth and high biodiversity.

Question 3: Explain the process of succession in a grassland ecosystem following a disturbance such as a fire.

Answer: After a fire, the grassland undergoes ecological succession. Initially, hardy grasses and herbaceous plants colonize the area. Over time, shrubs and small trees may establish, eventually leading to a mature grassland or woodland. This process involves changes in species composition and structure until a stable ecosystem is re-established.

Question 4: Identify three adaptations that plants in a desert ecosystem might have to survive in arid conditions.

Answer: Plants in deserts often have adaptations such as deep root systems to access underground water, small or spiny leaves to reduce water loss, and thick, waxy coatings on leaves to minimise evaporation.

Question 5: Describe the role of decomposers in maintaining a healthy forest ecosystem.

Answer: Decomposers, such as fungi and bacteria, break down dead organic matter, recycling nutrients back into the soil. This process enriches the soil, supports plant growth, and maintains the balance of nutrients within the forest ecosystem.

Question 6: Draw a simple diagram of a food chain in a freshwater pond ecosystem. Label the producer, primary consumer, and secondary consumer.

Answer: A correct sketch would show: a phytoplankton (producer) at the bottom, a small fish (primary consumer) feeding on phytoplankton, and a larger fish or bird (secondary consumer) feeding on the smaller fish. The diagram should clearly label each part.

Question 7: Explain how human activities, such as deforestation or pollution, can impact ecosystems.

Answer: Human activities like deforestation reduce habitat availability and biodiversity, leading to loss of species. Pollution contaminates air, water, and soil, harming plants and animals, disrupting food chains, and degrading ecosystem health. These impacts can cause long-term ecological changes and loss of ecosystem services.

Question 8: Identify and describe two key features of a tundra ecosystem.

Answer: The tundra features a cold climate with short summers and long, harsh winters. It has permafrost, a permanently frozen layer of soil, and supports low-growing vegetation such as mosses, lichens, and small shrubs adapted to extreme conditions.

Question 9: Sketch a diagram of a mountain ecosystem, including at least three different altitude zones. Label each zone and describe the typical vegetation found there.

Answer: The sketch should show a mountain with three altitude zones: lowland (broadleaf forests), mid-altitude (coniferous forests), and high-altitude (alpine tundra). Each zone should be labeled, with brief notes on typical vegetation: dense forests at lower levels, conifers in the middle, and sparse, hardy plants at high elevations.

Question 10: Discuss how climate change might affect polar ecosystems in the future.

Answer: Climate change causes rising temperatures, leading to melting ice and permafrost in polar regions. This reduces habitat for species like polar bears and seals, disrupts food chains, and causes loss of ice-dependent ecosystems. The changes can lead to decreased biodiversity and altered ecological balances.