Organisms and their Environment
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Energy flow
SubtopicEnergy flow under Organisms and their Environment for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
What is the main source of energy for a secondary consumer?
A.Sunlight
B.Primary consumers
C.Producers
D.Decomposers
- 2.
In a pyramid of biomass, which level is shown at the very top?
A.Producers
B.Primary consumers
C.Secondary consumers
D.The highest level consumer
- 3.
Which of the following is most likely to be at the top of a food chain?
A.A herbivore
B.A primary consumer
C.A carnivore
D.A producer
Download the worksheet for Organisms and their Environment - Energy flow to practice offline. It includes additional chapter-level practice questions.
Food chains and food webs
SubtopicFood chains and food webs under Organisms and their Environment for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
Why is biomass lost between trophic levels?
A.Because organisms do not eat every part of their prey
B.Because all organisms are the same size
C.Because producers have the least biomass
D.Because predators eat more than prey
- 2.
In a food chain, the first consumer is also called a:
A.Secondary consumer
B.Tertiary consumer
C.Primary consumer
D.Quaternary consumer
- 3.
If a disease kills most of the rabbits in a field, what might happen to the foxes that eat them?
A.The fox population will increase
B.The fox population will decrease or find new prey
C.The foxes will start eating grass
D.Nothing will change
Download the worksheet for Organisms and their Environment - Food chains and food webs to practice offline. It includes additional chapter-level practice questions.
Nutrient cycles (Carbon and Nitrogen)
SubtopicNutrient cycles (Carbon and Nitrogen) under Organisms and their Environment for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
Which chemical element is found in all proteins, DNA, and RNA, but is NOT found in simple carbohydrates like glucose?
A.Carbon
B.Hydrogen
C.Oxygen
D.Nitrogen
- 2.
In the nitrogen cycle, which process is inhibited by plowing or turning the soil to add oxygen?
A.Nitrification
B.Denitrification
C.Nitrogen fixation
D.Decomposition
- 3.
Which of these is a biotic factor that moves carbon through an ecosystem?
A.Volcanic activity
B.Weathering of rocks
C.Respiration
D.Combustion of coal
Download the worksheet for Organisms and their Environment - Nutrient cycles (Carbon and Nitrogen) to practice offline. It includes additional chapter-level practice questions.
Populations
SubtopicPopulations under Organisms and their Environment for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
Which process describes how plants use light energy to make their own food?
A.Respiration
B.Photosynthesis
C.Transpiration
D.Combustion
- 2.
In a food web, if a top predator is removed, what is most likely to happen to the population of its prey?
A.It will decrease immediately
B.It will increase
C.It will stay exactly the same
D.It will become extinct
- 3.
Which of these is a renewable resource?
A.Coal
B.Natural gas
C.Wind energy
D.Oil
Download the worksheet for Organisms and their Environment - Populations to practice offline. It includes additional chapter-level practice questions.