Conservation, Systems & Environmental Design — Chapter quiz · Physics & Environmental Science, Grade 12

Join conservation evidence, feedback, risk, and a complete design-and-monitoring proposal.

Problem 1

The leading cause of species extinction today is
  1. habitat loss and fragmentation
  2. the existence of zoos
  3. scientists studying wildlife
  4. the natural aging of individual animals
Answer and explanation

habitat loss and fragmentation

Destroying and dividing natural habitat is the single largest driver of biodiversity loss worldwide.

Problem 2

Which scenario is an example of overexploitation?
  1. A wetland is paved over to build a parking lot
  2. A fish population is caught faster than it can reproduce, and it collapses
  3. A non-native beetle spreads through a forest with no natural predators
  4. Fertilizer runs off a field into a river
Answer and explanation

A fish population is caught faster than it can reproduce, and it collapses

Harvesting a species faster than it can replace itself is overexploitation; the other choices are habitat loss, an invasive species, and pollution.

Problem 3

Which of the following is a strategy for living more sustainably?
  1. Clearing more forest for short-term profit
  2. Using resources faster than they can be replaced
  3. Replacing fossil-fuel power plants with wind and solar energy
  4. Increasing the amount of waste sent to landfills each year
Answer and explanation

Replacing fossil-fuel power plants with wind and solar energy

Shifting to renewable energy cuts emissions and reduces our draw on finite resources; the other choices all increase environmental harm.

Problem 4

In a hypothetical ecological-footprint model, demand is 1.7 times reference regenerative capacity. What does this ratio mean?
Answer and explanation

0.7 Earths

Demand is 70% above the stated reference in that model; it is not a current undated global observation.

Problem 5

Explain the following claim and supply a valid example or counterexample: Non-native does not automatically mean invasive; harmful establishment/spread needs evidence.
Answer and explanation

They can improve movement and gene flow but also transport disease or invasives; compare evidence and target species. Non-native does not automatically mean invasive; harmful establishment/spread needs evidence.

Response criteria

  • State a scientifically accurate conclusion.
  • Show the calculation or mechanism that supports it.
  • Include units, conditions, or limits where relevant.

Problem 6

Independent chapter check: A population estimate falls from500 to350 under comparable methods. Find percent decline. Explain why this does not prove global extinction or identify a unique cause.
Answer and explanation

Decline=(500−350)/500=30%. Living individuals remain in the defined population, and the record alone cannot distinguish survival, reproduction, movement or the pressures affecting them.

Decline=(500−350)/500=30%.

Living individuals remain in the defined population, and the record alone cannot distinguish survival, reproduction, movement or the pressures affecting them.

Response criteria

  • Use the stated measurements or conditions, with correct units.
  • Connect the result to the physical or environmental mechanism or evidence relationship.
  • Identify the assumption, model limit or further evidence requested.

Problem 7

Explain the following claim and supply a valid example or counterexample: No energy technology is impact-free across extraction, manufacture, use, and disposal.
Answer and explanation

A baseline, defined service and boundary, predicted outcomes, resource/impact accounting, trade-offs, and monitoring. No energy technology is impact-free across extraction, manufacture, use, and disposal.

Response criteria

  • State a scientifically accurate conclusion.
  • Show the calculation or mechanism that supports it.
  • Include units, conditions, or limits where relevant.

Problem 8

Independent chapter check: Energy per use falls from10 to6 units while annual uses rise from100 to140. Find old/new total and percent saving; state a separate service criterion.
Answer and explanation

Old=1000 units; new=840; saving=160 units=16%, smaller than the40% per-use reduction. Adequate service quality, access or reliability needs a separate measure.

Old=1000 units; new=840; saving=160 units=16%, smaller than the40% per-use reduction.

Adequate service quality, access or reliability needs a separate measure.

Response criteria

  • Use the stated measurements or conditions, with correct units.
  • Connect the result to the physical or environmental mechanism or evidence relationship.
  • Identify the assumption, model limit or further evidence requested.

Problem 9

Identify a negative feedback in a water-tank controller.
Answer and explanation

A higher level triggers less inflow or more outflow, opposing the initial increase.

Response criteria

  • State a scientifically accurate conclusion.
  • Show the calculation or mechanism that supports it.
  • Include units, conditions, or limits where relevant.

Problem 10

Why include stakeholder impacts in a design?
Answer and explanation

Costs and risks can be unevenly distributed even when total modeled benefit is positive.

Response criteria

  • State a scientifically accurate conclusion.
  • Show the calculation or mechanism that supports it.
  • Include units, conditions, or limits where relevant.

Problem 11

Independent chapter check: Event A has probability0.05 and consequence200 units; B has probability0.20 and consequence40. Find expected losses and explain why the smaller expected value need not settle the choice.
Answer and explanation

A=10 units; B=8 units. B has lower expected loss, but worst-case severity, uncertainty, distribution, constraints and priorities still need transparent consideration.

A=10 units; B=8 units.

B has lower expected loss, but worst-case severity, uncertainty, distribution, constraints and priorities still need transparent consideration.

Response criteria

  • Use the stated measurements or conditions, with correct units.
  • Connect the result to the physical or environmental mechanism or evidence relationship.
  • Identify the assumption, model limit or further evidence requested.

Problem 12

Name a factor that could confound before/after heating-energy comparison.
Answer and explanation

Different weather, occupancy, building area, or meter methods.

Response criteria

  • State a scientifically accurate conclusion.
  • Show the calculation or mechanism that supports it.
  • Include units, conditions, or limits where relevant.

Problem 13

What distinguishes a justified recommendation from a slogan?
Answer and explanation

Quantified evidence, mechanism, assumptions, alternatives, trade-offs, sensitivity, and a test plan.

Response criteria

  • State a scientifically accurate conclusion.
  • Show the calculation or mechanism that supports it.
  • Include units, conditions, or limits where relevant.

Problem 14

Independent chapter check: A proposed change saves12 W for1500 h/year while providing the same service. Its extra production energy is24 kWh. Find annual saving and energy break-even; name one pilot measure beyond energy.
Answer and explanation

Annual saving=0.012×1500=18 kWh. Energy break-even=24/18≈1.33 years under fixed use/lifespan assumptions. Measure service adequacy, reliability, actual hours, access or maintenance as a separate pilot outcome.

Annual saving=0.012×1500=18 kWh.

Energy break-even=24/18≈1.33 years under fixed use/lifespan assumptions.

Measure service adequacy, reliability, actual hours, access or maintenance as a separate pilot outcome.

Response criteria

  • Use the stated measurements or conditions, with correct units.
  • Connect the result to the physical or environmental mechanism or evidence relationship.
  • Identify the assumption, model limit or further evidence requested.

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