Ecology and the Environment

Worked examples (6)

• 1Define a population (Getting started)
• 2Define a habitat (Getting started)
• 3Population versus community (Building confidence)
• 4Define an ecosystem (Building confidence)
• 5Classify the parts of a pond (Stretch)
• 6Biotic and abiotic factors in an ecosystem (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Name the apparatus and the term (Getting started)
• 2Why place quadrats randomly (Getting started)
• 3Calculate the population estimate (Building confidence)
• 4Using a transect along a gradient (Building confidence)
• 5Evaluate and improve the method (Stretch)
• 6Plan a comparison of two areas (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — calculation
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Abiotic or biotic? (Getting started)
• 2Name abiotic and biotic factors (Getting started)
• 3Light and plant numbers (Building confidence)
• 4Predator–prey cycle (Building confidence)
• 5Soil pH and distribution (Stretch)
• 6Explain a multi-factor scenario (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Define a trophic level (Getting started)
• 2Define a producer (Getting started)
• 3Name the consumers in a chain (Building confidence)
• 4Decomposers and their role (Building confidence)
• 5Label a whole food chain (Stretch)
• 6What the arrows mean (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Read a food chain (Getting started)
• 2What each pyramid shows (Getting started)
• 3Why a pyramid of number is an odd shape (Building confidence)
• 4Effect of removing an organism (Building confidence)
• 5Why a pyramid of biomass is a true pyramid (Stretch)
• 6Choosing the right pyramid (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Read a food chain (Getting started)
• 2Ways energy is lost (Getting started)
• 3Why food chains are short (Building confidence)
• 4Substances along the chain (Building confidence)
• 5Explain the low energy at the top (Stretch)
• 6Tracking energy up the chain (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Name the process that removes CO₂ (Getting started)
• 2Which way does each process move carbon? (Getting started)
• 3How decomposition returns carbon (Building confidence)
• 4Combustion and the fossil-fuel store (Building confidence)
• 5Describe the stages of the carbon cycle (Stretch)
• 6Why burning fuel raises CO₂ (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Name greenhouse gases (Getting started)
• 2Match the activity to the gas (Getting started)
• 3How the greenhouse effect keeps the Earth warm (Building confidence)
• 4Why deforestation raises CO₂ (Building confidence)
• 5From extra gases to global warming (Stretch)
• 6Consequences of global warming (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Name pollutants from burning fossil fuels (Getting started)
• 2State the effects of acid rain (Getting started)
• 3Why acid rain kills fish (Building confidence)
• 4How carbon monoxide affects the blood (Building confidence)
• 5Why carbon monoxide can be fatal (Stretch)
• 6Compare sulfur dioxide and carbon monoxide (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response

Worked examples (6)

• 1Why sewage kills fish (Getting started)
• 2Name the eutrophication minerals (Getting started)
• 3Put eutrophication in order (Building confidence)
• 4Sewage and the spread of disease (Building confidence)
• 5Explain death of fish from fertiliser run-off (Stretch)
• 6Compare sewage and eutrophication (Stretch)

Model answers (6)

• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style
• ✓Model answer — 4WSD0/1B style — extended open response
• ✓Model answer — 4WSD0/1B style — extended open response