Q: What does EXTENSION TOPICS, Topic B - Impact of Climate Change on Animals and Plants cover?
A: Analyse how greenhouse emissions reshape ecosystems, food security, biodiversity, and disease vectors so you can deliver data-driven answers for the H2 Biology climate change extension topic.
Why this topic matters for future-facing biology
Systems thinking: Questions integrate ecology, physiology, biotechnology, and socio-economics.
Data analysis: Expect graphs on temperature trends, crop yields, carbon budgets, or dengue incidence.
Singapore context: Local mangroves, urban heat islands, and vector control are common framing devices.
Syllabus map
Anthropogenic greenhouse gas sources (COX2, methane)
Interpret a multiple-variable graph showing temperature anomalies, sea-level rise, and atmospheric COX2. Explain causal relationships and potential confounders.
Concept 3: Ecosystem services and mitigation
Mangroves: Carbon sequestration (blue carbon), shoreline protection, nursery habitats for fish. Explain root adaptations (pneumatophores) and role in buffering storm surges.
Seagrass and mangroves synergy: Capture sediments, maintain water clarity, support biodiversity.
Encourage using units such as kgCOX2 equivalent per kilogram of product. Include discussion on technological mitigation (precision fermentation, vertical farming).
Concept 5: Food security and biodiversity
Crop stress: Heat and drought reduce yields; pests expand ranges; discuss C3 vs C4 plant responses.
Livestock: Heat stress reduces productivity and increases disease susceptibility.
Global food supply: Supply chain disruptions, reliance on climate-sensitive staples, need for climate-resilient crops (drought-tolerant rice, heat-tolerant wheat).
Biodiversity loss: Tropical rainforests host genetic resources; extinction erodes potential for new medicines and resilient crop genes.
Case evaluation
Assess how a 2∘C temperature rise might alter Southeast Asian rice yields, referencing evapotranspiration rates and pest pressures.
Concept 6: Climate impacts on insects and disease
Metabolism and temperature:Q10 effect increases metabolic rates, shortening reproduction cycles for insects.
Aedes aegypti life cycle: Higher temperatures shorten egg-to-adult duration, expanding vector populations; discuss breeding grounds (urban stagnant water).
Range expansion: Warmer climates enable mosquitoes to colonise higher altitudes/latitudes; dengue and malaria risk spread.
Disease modelling: Link to R0 increases when vector density rises; emphasise vector control strategies adapting to climate change (source reduction, Wolbachia programmes, genetically modified mosquitoes).
Data interpretation
Given a dataset correlating weekly temperature with dengue case counts, calculate correlation coefficients, discuss lag effects, and propose public health interventions.
Exam technique and synthesis
Paper 2: Be ready for short-answer justifications of mitigation strategies or interpreting carbon footprint graphs.
Paper 3: Prepare essays such as “Evaluate how climate change threatens biodiversity and food security in tropical regions.”
Paper 4/Data handling: Practise planning investigations on plant stress physiology (chlorophyll fluorescence vs temperature) or analysing dengue incidence data; outline control variables, risk assessments, and improvement suggestions.
Closing the series
Link back to infectious diseases and evolution: climate shifts influence pathogen dynamics and selection pressures. Maintain an interdisciplinary mindset for integrative questions in the H2 Biology papers.
EXTENSION TOPICS, Topic B - Impact of Climate Change on Animals and Plants
