Life Sciences - Term 3 - Week 9

An ecosystem consists of living organisms (biotic factors) and non-living elements (abiotic factors) that interact with each other. Biotic factors include plants, animals, fungi, and microorganisms, while abiotic factors encompass sunlight, water, soil, and climate. These components work together to create a balanced environment where energy flows and nutrients cycle. For instance, plants (producers) convert sunlight into energy through photosynthesis, which is then passed on to herbivores (primary consumers) and subsequently to carnivores (secondary consumers).

Biodiversity refers to the variety of life in a particular habitat or ecosystem. It is crucial for ecosystem resilience, allowing ecosystems to withstand environmental changes and recover from disturbances. High biodiversity contributes to ecosystem services such as pollination, nutrient cycling, and climate regulation. The loss of biodiversity can lead to ecosystem collapse, affecting food security and human health. Therefore, conserving biodiversity is essential for sustainable development and environmental health.

Consider a simple food chain: grass → rabbit → fox. In this chain, grass is a producer that converts sunlight into energy. The rabbit, as a primary consumer, feeds on the grass, obtaining energy for growth and reproduction. The fox, a secondary consumer, preys on the rabbit, illustrating the flow of energy through the ecosystem. Each organism plays a vital role, and the removal of one can disrupt the entire chain.

In pairs, students will be given a list of organisms from a specific ecosystem (e.g., a forest). They will categorize these organisms into producers, primary consumers, secondary consumers, and decomposers. After categorizing, each pair will present their findings to the class, explaining the role of each organism and how they contribute to the ecosystem's health.

Students will choose a local ecosystem (e.g., a river, forest, or urban area) and conduct research on its biodiversity. They will create a poster that includes the types of organisms found, their roles in the ecosystem, and any threats to biodiversity in that area. Students will present their posters to the class, fostering discussion on conservation efforts.

• An organism that eats other organisms
• An organism that produces its own food
• An organism that decomposes dead matter
• An organism that competes for resources

Answer: An organism that produces its own food

Producers, such as plants, convert sunlight into energy through photosynthesis.

• Grass
• Rabbit
• Fox
• Fungi

Answer: Rabbit

Primary consumers are herbivores that feed on producers like grass.

Answer: Biodiversity is the variety of life in a particular habitat or ecosystem.

Biodiversity includes the diversity of species, genetic variations, and ecosystems.

• They produce energy
• They consume primary consumers
• They break down dead organic matter
• They compete with producers

Answer: They break down dead organic matter

Decomposers recycle nutrients back into the ecosystem by breaking down dead organisms.

Answer: Habitat destruction due to urbanization reduces the number of species in an area.

As natural habitats are destroyed, many species lose their homes and food sources, leading to declines in biodiversity.

• Plants
• Animals
• Soil
• Fungi

Answer: Soil

Soil is an abiotic factor, while plants, animals, and fungi are biotic factors.

• Water
• Soil
• Sunlight
• Wind

Answer: Sunlight