DP Biology Questionbank

• Syllabus

Option C: Ecology and conservation (Core topics)

Sub sections and their related questions

C.1 Species and communities

• 15M.3.HL.TZ1.11a: Distinguish between the use of a quadrat and a transect in gathering field data.
• 15M.3.SL.TZ1.20a: Describe how a transect can be used to investigate the distribution of plant species in this...
• 15M.3.SL.TZ1.21b: Explain the concept of niche.
• 15N.3.SL.TZ0.21b: Explain what is meant by the niche concept.
• 13M.3.SL.TZ2.20a: Explain the niche concept.
• 11M.3.SL.TZ1.20a: Define the terms fundamental niche and realized niche.   Fundamental niche:...
• 11M.3.SL.TZ2.20a: Explain the concept of an ecological niche.
• 11M.3.SL.TZ2.20b: Distinguish between fundamental niches and realized niches.
• 12M.3.SL.TZ1.21b: Explain how temperature and territory affect the distribution of animal...
• 12M.3.SL.TZ2.20a: Biotic factors involve the other organisms in the environment of an animal species. List two...
• 10M.3.SL.TZ1.27a: Outline three factors that affect plant distribution.
• 10M.3.SL.TZ1.27b: Outline a method used to correlate the distribution of plant species with an abiotic factor.
• 10M.3.SL.TZ2.20a: List four factors that affect the distribution of plant species.
• 10M.3.SL.TZ2.20b: Describe one effect of plants on an abiotic factor in a pioneer community.  
• 11N.3.SL.TZ0.19a: List two abiotic factors that affect the distribution of plant species. 1. ...
• 11N.3.SL.TZ0.19b: State one example of secondary succession.
• 11N.3.SL.TZ0.19c: Distinguish between fundamental and realized niches.
• 12N.3.HL.TZ0.10d: State two types of interactions that are most likely to occur among deep-water fish. 1....
• 12N.3.SL.TZ0.21b: Water is one factor that affects the distribution of plant species. Outline three other factors...
• 10N.3.SL.TZ0.19a: State the week number when the highest human biting rate (HBR) is found for A. gambiae.
• 10N.3.SL.TZ0.20b: Calculate the difference in peak HBR for A. gambiae and A. funestus for week 6.
• 10N.3.SL.TZ0.6c: Evaluate the effect of increased precipitation on HBR for both species.
• 10N.3.SL.TZ0.20d: Suggest how predictions of global climate changes, such as predictions of precipitation patterns,...
• 10N.3.SL.TZ0.20e: Suggest another factor which might affect the ecological distribution of mosquitoes.
• 10N.3.SL.TZ0.21a: Distinguish between fundamental niches and realized niches.
• 10N.3.HL.TZ0.10a: State the week number when the highest human biting rate (HBR) is found for A. gambiae.
• 10N.3.HL.TZ0.10b: Calculate the difference in peak HBR for A. gambiae and A. funestus for week 6.
• 10N.3.HL.TZ0.10c: Evaluate the effect of increased precipitation on HBR for both species.
• 10N.3.HL.TZ0.10d: Suggest how predictions of global climate changes, such as predictions of precipitation patterns,...
• 10N.3.HL.TZ0.10e: Suggest another factor which might affect the ecological distribution of mosquitoes.
• 16M.3.HL.TZ0.15a: Using graph A and graph B, compare and contrast the temperature ranges of the two species when...
• 16M.3.HL.TZ0.15b: Explain, with respect to the example of P. montenegrina, what is meant by realized niche.
• 16N.3.SL.TZ0.11a: Distinguish between a fundamental niche and realized niche.
• 16N.3.SL.TZ0.11c: Describe how the distribution of Chthamalus and Balanus is affected when both are present.
• 16N.3.SL.TZ0.14a: Outline the trend in the number of people with malaria during the period when the use of...
• 16N.3.HL.TZ0.14: Cryptococcus neoformans and the closely related species Cryptococcus gattii are human fungal...
• 17M.3.SL.TZ1.13a: State the relationship between Zooxanthellae and coral reef species.
• 17M.3.SL.TZ1.13b: Describe the exchange of materials between the coral’s polyps and Zooxanthellae.
• 17M.3.SL.TZ1.13c: State one limiting factor on Zooxanthellae which affects coral reef formation.
• 17M.3.SL.TZ2.14: Paramecium aurelia and Paramecium caudatum are single cell organisms. They were grown separately...
• 17M.3.SL.TZ2.17c: Researchers have argued that S. geminata is a keystone species in the corn agricultural system....
• 17M.3.HL.TZ2.15a: State the type of interaction that occurs between Zooxanthellae and reef-building corals.
• 17N.3.SL.TZ0.15: Explain reasons for differences in the realized niche and fundamental niche of an organism.
• 17N.3.HL.TZ0.17a.i: Define fundamental niche.
• 17N.3.HL.TZ0.17a.ii: Outline a reason for organisms seldom occupying their entire fundamental niche.
• 17N.3.HL.TZ0.17b: Describe the relationship between Zooxanthellae and reef-building coral species.

C.2 Communities and ecosystems

• 15M.3.HL.TZ1.11b (i): State the change in species diversity and the change in production during primary...
• 15M.3.HL.TZ1.11b (ii): State one difficulty in classifying organisms into trophic levels.
• 15M.3.SL.TZ1.20b: The vegetation shown here has developed as a result of primary succession. Outline the changes...
• 15N.3.SL.TZ0.20b: Explain how living organisms can change the abiotic environment during primary succession.
• 15N.3.HL.TZ0.11c: Explain how living organisms can change the abiotic environment during primary succession.
• 13N.2.HL.TZ0.3a: (i) Label the diagram to complete the food web for the organisms in the table above.  (ii)  ...
• 13M.3.SL.TZ1.19a (i): State the most ruderal species.
• 13M.3.SL.TZ1.19a (ii): Species number 4 has a ruderalism value of 29.  State the stress-tolerance value and...
• 13M.3.SL.TZ1.19b: Analyse the change of species over time.
• 13M.3.SL.TZ1.21a: Discuss the difficulties of classifying organisms into trophic levels.
• 13N.3.SL.TZ0.19a: State the grass species that is most abundant in plant community 1.
• 13N.3.SL.TZ0.19b: Analyse the graph to find whether species 45 has a broad or narrow realized niche.
• 13N.3.SL.TZ0.19c.i: Suggest a reason for this in community 1.
• 13N.3.SL.TZ0.19c.ii: Suggest a reason for this in community 17.
• 13N.3.SL.TZ0.19d: Evaluate the conclusion that there are trends in the distribution of plants along the transect of...
• 13N.3.SL.TZ0.20b.i: State the type of ecological change that will occur following the formation of an island from...
• 13N.3.SL.TZ0.20b.ii: Outline the ecological changes that will occur on the island of cooled lava.
• 11M.2.HL.TZ2.4a (i): Identify an organism in the food web that is an autotroph. 
• 11M.2.HL.TZ2.4a (ii): Identify an organism in the food web that is both a secondary and tertiary consumer.
• 11M.2.HL.TZ2.4b: Explain how the flow of energy in the food web differs from the movement of nutrients.
• 12M.3.HL.TZ1.11a: In a grassland ecosystem, the amount of energy captured by the photosynthetic organisms was 100...
• 12M.3.HL.TZ1.11b: Define biomass.
• 12M.3.HL.TZ2.11a: Outline changes in species diversity during primary succession.
• 12M.3.SL.TZ2.20b: Research into a river ecosystem produced these approximate values: 25, 300, 6000 and 36 000 kJ...
• 12M.3.SL.TZ2.21a: Explain how living organisms can affect the abiotic environment during primary succession.
• 10M.3.HL.TZ1.11a: Identify the trophic level of the toad.
• 10M.3.SL.TZ2.20b: Describe one effect of plants on an abiotic factor in a pioneer community.  
• 11N.3.HL.TZ0.11a: Identify, with a reason, the type of succession that has taken place.
• 11N.3.SL.TZ0.19d: Discuss the difficulties of classifying organisms into trophic levels.
• 12N.3.HL.TZ0.11b (ii): Define the term biomass.
• 10N.3.SL.TZ0.2b: Describe a primary succession in a named type of habitat.
• 10N.3.SL.TZ0.3a: Label the levels of the trophic pyramid of energy shown below.
• 10N.3.HL.TZ0.11a: Earthworms are primary consumers that can be grown on household food waste such as fruit and...
• 10N.3.HL.TZ0.11b: State the units used in a pyramid of energy.
• 09N.3.SL.TZ0.20b: State the units used in a pyramid of energy.
• 09N.3.SL.TZ0.20c: Explain the small biomass of organisms in higher trophic levels.
• 16M.3.HL.TZ0.16a: Describe the change in biomass over the 100 year period.
• 16M.3.HL.TZ0.16b: Outline the evidence from the graph that the area had plentiful rainfall.
• 16M.3.HL.TZ0.16c: Explain the changes in biomass.
• 16M.3.HL.TZ0.16d: Explain why biomass continues to increase after the respiration levels plateau.
• 16M.3.SL.TZ0.14a: Primary plant succession has been observed in sand dunes adjacent to the northern end of Lake...
• 16M.3.SL.TZ0.14b: Outline how the type of stable ecosystem that will develop in an area can be predicted based on...
• 16N.3.SL.TZ0.12a: Identify the ecosystem with the appropriate numeral from the climograph.
• 16N.3.SL.TZ0.12b: Referring to the climograph, explain reasons that the nutrient store in the litter layer of the...
• 16N.3.SL.TZ0.14a: Outline the trend in the number of people with malaria during the period when the use of...
• 17M.3.SL.TZ1.14: The Gersmehl diagram below shows the movement and storage of nutrients in a taiga...
• 17M.3.HL.TZ1.13c: Distinguish between mutualism and parasitism, providing another example of mutualism and another...
• 17M.3.HL.TZ1.14e: Determine whether islands are open or closed ecosystems.
• 17M.3.SL.TZ2.16a: Estimate the approximate amount of biomass represented by parasites in this ecosystem.
• 17M.3.SL.TZ2.16b: Compare and contrast the biomass in the different trophic levels.
• 17M.3.SL.TZ2.16c: Outline the reason that parasite biomass occurs in both tertiary consumers and secondary consumers.
• 17M.3.SL.TZ2.17a: State the impact of S. geminata on insect species diversity.
• 17M.3.SL.TZ2.17b: Discuss whether S. geminata might play a positive role in corn production.
• 17M.3.HL.TZ2.15b: State the trophic level of Zooxanthellae.
• 17M.3.HL.TZ2.17: Distinguish between tropical rainforest and taiga in terms of nutrient stores, nutrient flows and...
• 17N.3.SL.TZ0.12a: Calculate the energy loss due to respiration in primary consumers in kJ m–2 y–1.
• 17N.3.SL.TZ0.12b: Outline why a year is more suitable than a month for the measurement of energy flow.
• 17N.3.SL.TZ0.13b: The sea star also eats the sea snails. Construct a food web to show the feeding relationships...

C.3 Impacts of humans on ecosystems

• 15M.3.SL.TZ2.21a : Outline one example of biological control of a named invasive species.
• 15M.3.HL.TZ1.10a: State the depth range showing the most Bythotrephes during the night.
• 15M.3.HL.TZ1.10b: Describe the distribution of Bythotrephes during the day.
• 15M.3.HL.TZ1.10c: Deduce the responses of Bythotrephes to temperature and light.
• 15M.3.HL.TZ1.10d: Explain the change in distribution of Bythotrephes between day and night in terms of its position...
• 15M.3.SL.TZ1.21a: Explain the causes and consequences of biomagnification of a named chemical.
• 15M.3.HL.TZ2.10a: Identify the site with the lowest average CFU of E. coli in the water samples.
• 15M.3.HL.TZ2.10b: Distinguish between the trends in the survival of E. coli on mat samples and in water samples...
• 15M.3.HL.TZ2.10c: Scientists formerly related the population of Cladophora to changes in phosphorous levels in the...
• 15M.3.HL.TZ2.10d: Discuss the possible ecological relationships between E. coli and Cladophora.
• 15N.3.SL.TZ0.21a: State the process where pesticides such as DDT become more concentrated at each trophic level.
• 15N.3.HL.TZ0.10f: Discuss whether the results for the Varied Tit and Coal Tit indicate competitive exclusion.
• 15N.3.HL.TZ0.12: Discuss, using three examples, how alien species have impacted ecosystems.
• 13M.3.HL.TZ1.10a: State the trophic level of the fish that presents the least risk of mercury contamination for...
• 13M.3.HL.TZ1.10b: Compare the levels of mercury found in herbivores (primary consumers) and detritivores.
• 13M.3.HL.TZ1.10c: Explain the large range of mercury concentrations seen in the piscivores.
• 13M.3.HL.TZ1.1d: Discuss how an understanding of biomagnification could help these human populations reduce their...
• 13M.3.HL.TZ2.12: Explain the causes and consequences of biomagnification with reference to a named example.
• 13M.3.SL.TZ1.21b: Explain the cause and consequences of biomagnification, using a named example.
• 11M.3.HL.TZ2.10a: Identify the highest average concentration of cadmium found in P. peltifer.
• 11M.3.HL.TZ2.10b: Determine, with a reason from the data, which species is unable to eliminate cadmium.
• 11M.3.HL.TZ2.10c (i): State the species that accumulates the least cadmium.
• 11M.3.HL.TZ2.10c (ii): Suggest, with observations from the data, a reason why the species stated in (c)(i) accumulates...
• 11M.3.HL.TZ2.10d: Describe the possible effects of the presence of cadmium in food chains involving these arthropods.
• 11M.3.SL.TZ1.20c: Explain why carnivores tend to be more affected by biomagnification than organisms lower down the...
• 11M.3.SL.TZ1.21a: The introduction of alien species and the release of environmental pollutants are examples of...
• 12M.3.HL.TZ2.11c: (i)  Describe the environmental impact of a named invasive alien species.   (ii)  State an...
• 12M.3.SL.TZ2.21b: State one example of biological control of an invasive species.   Invasive species: ...
• 12M.3.SL.TZ2.21c: Define biomagnification.
• 10M.3.HL.TZ1.10a: Using the data in the graph, describe the accumulation of arsenic in the Chinese brake fern.
• 10M.3.HL.TZ1.10b (i): Assuming the mean rate of arsenic accumulation over the first 20 weeks continued, calculate how...
• 10M.3.HL.TZ1.10b (ii): Using the data in the table, discuss the potential of using Chinese brake fern to remove arsenic...
• 10M.3.HL.TZ1.10c: Suggest one possible consequence of arsenic accumulation in plants for other organisms in the...
• 10M.3.SL.TZ1.28a : State one example of the accidental release of an alien species that has had a significant impact...
• 10M.3.SL.TZ1.28b: Discuss the impact of alien species on ecosystems.
• 12N.3.HL.TZ0.11a: Define the term biomagnification.
• 12N.3.SL.TZ0.20a: Explain the principal of competitive exclusion.
• 12N.3.SL.TZ0.20b (ii): Using a named example, explain a consequence of biomagnification.
• 10N.3.SL.TZ0.22b: Discuss the impact of alien species on the environment.
• 09N.3.HL.TZ0.11a(i): Define biomagnification.
• 09N.3.HL.TZ0.11a(ii): Outline a named example of biomagnification.
• 10N.3.HL.TZ0.10f: Suggest a biological control that might be introduced to reduce HBR.
• 09N.3.SL.TZ0.21a: Discuss the impacts of a named alien species introduced as a biological control measure.
• 16M.3.HL.TZ0.17a: Suggest one reason for the Laysan Albatross ingesting indigestible plastic.
• 16M.3.HL.TZ0.17b: Suggest a reason for the difference in ingested plastic in the diets of the Laysan Albatross in...
• 16M.3.HL.TZ0.17c: Outline the origin of microplastic debris in the marine environment.
• 16M.3.HL.TZ0.17d: Using microplastics as an example, outline the concept of biomagnification.
• 16M.3.SL.TZ0.15a: Outline how biomagnification occurs.
• 16M.3.SL.TZ0.15b: (i) Identify the predator with the least biomagnification of pollutants. (ii) Suggest a reason...
• 16M.3.SL.TZ0.15c: Deduce two conclusions about PCBs that are supported by the data.
• 16M.3.SL.TZ0.16: Explain how alien species can affect community structure in an ecosystem.
• 16N.3.SL.TZ0.14a: Outline the trend in the number of people with malaria during the period when the use of...
• 16N.3.SL.TZ0.14b: One pesticide used in killing mosquitoes was DDT. Considering its harmful effects,...
• 16N.3.HL.TZ0.15a: Predict one example of macroplastic pollution that is likely to be found in this lake.
• 16N.3.HL.TZ0.15b: State two possible effects on organisms of microplastic pollution.
• 16N.3.HL.TZ0.15c: Outline the effect of wind on the distribution of plastic pollution in this lake.
• 16N.3.HL.TZ0.15d: Suggest changes in the management of the national park that could reduce the amount of...
• 17M.3.SL.TZ1.15a: Outline one consequence of introducing an alien species into an ecosystem.
• 17M.3.SL.TZ1.15b: State the origin of cane toads.
• 17M.3.SL.TZ1.15c: Evaluate the use of traps containing toxin as a means of cane toad control.
• 17M.3.HL.TZ1.14c: Indicator species may be affected by biomagnification. Discuss biomagnification using a named...
• 17N.3.SL.TZ0.12c: Explain how pesticides may undergo biomagnification in the lake.
• 17N.3.SL.TZ0.13a: Compare and contrast the effects of the predators on the population of the mussels.
• 17N.3.HL.TZ0.14a.i: Identify how the pattern in mammals is different from reptiles and birds.
• 17N.3.HL.TZ0.14a.ii: Describe how invasive species such as F. silvestris can have a significant impact on native species.
• 17N.3.HL.TZ0.14a.iii: Suggest a method to limit the impact of F. silvestris on native species.
• 17N.3.HL.TZ0.16c: Outline three issues arising from the release of pollutants into the environment.  

C.4 Conservation of biodiversity

• 15N.3.HL.TZ0.11b: Outline how habitat corridors can aid conservation of biodiversity in a nature reserve.
• 13M.3.HL.TZ1.11c: Outline the biogeographical features of nature reserves that promote the conservation of diversity.
• 13M.3.HL.TZ1.11: Discuss how international efforts can contribute to the conservation of fish stocks.
• 13M.3.HL.TZ2.11a: Distinguish between in situ and ex situ conservation.
• 13M.3.HL.TZ2.11d: Outline one reason for the extinction of a named animal species.
• 13M.3.SL.TZ2.20c: Outline one reason for the extinction of a named animal species
• 13N.3.HL.TZ0.12: Eight sub-species of tigers existed in 1950, but three of these former sub-species have now...
• 13N.3.SL.TZ0.21b.i: State what \(N\) and \(n\) stand for in this formula.   \(N\):   \(n\):
• 13N.3.SL.TZ0.21b.ii: Discuss three reasons for the conservation of biodiversity in rainforests.
• 11M.3.HL.TZ1.11b: Outline the consequences of the edge effect for small nature reserves.
• 11M.3.HL.TZ2.11b: Define indicator species.
• 11M.3.HL.TZ2.11c: Outline, with a named example, biological control of invasive species.
• 12M.3.HL.TZ1.12: Discuss the advantages of in situ conservation of endangered species, using examples.
• 12M.3.HL.TZ2.12: Explain, with examples, the use of specific indicator species and biotic indices to detect...
• 10M.3.HL.TZ1.12: Evaluate the use of indicator species in monitoring environmental changes.
• 10M.3.SL.TZ2.21a: State the name of a statistical method used to quantify changes in biodiversity.
• 10M.3.SL.TZ2.3b: Discuss reasons for conservation of biodiversity of a named ecosystem.
• 11N.3.HL.TZ0.11d: Yellowstone National Park was the first national park in the world and is a designated biosphere...
• 11N.3.HL.TZ0.12: Discuss international measures that would promote the conservation of fish stocks.
• 09N.3.HL.TZ0.12: Discuss international measures that would promote the conservation of fish, including methods...
• 10N.3.HL.TZ0.12: Discuss the role of ex situ conservation of endangered species.
• 16N.3.SL.TZ0.13a: Compare and contrast the richness and the evenness of the two fields.
• 16N.3.SL.TZ0.14a: Outline the trend in the number of people with malaria during the period when the use of...
• 16N.3.HL.TZ0.16b: Outline how the edge effect can affect diversity in forests.
• 16N.3.HL.TZ0.16c: The number of plants in two fields of approximately the same size was counted. Compare and...
• 16N.3.SL.TZ0.13b: A calculation of Simpson’s reciprocal index was undertaken on each field with the following...
• 17M.3.SL.TZ1.16a: Calculate the diversity of site C. Working should be shown.
• 17M.3.SL.TZ1.16b: Site A has a higher Simpson’s reciprocal index than Site B showing that its diversity is...
• 17M.3.SL.TZ1.16c: Discuss the advantages and disadvantages of in situ conservation methods.
• 17M.3.HL.TZ1.14b: Define indicator species.
• 17M.3.HL.TZ1.14c: Indicator species may be affected by biomagnification. Discuss biomagnification using a named...
• 17M.3.HL.TZ1.15b: Discuss two advantages of ex situ conservation measures. 
• 17M.3.HL.TZ1.15c: State the two components needed to calculate the biodiversity of an area.
• 17M.3.SL.TZ2.18: Explain the use of indicator species to assess the condition of the environment.
• 17M.3.HL.TZ2.15c: When coral is bleached, certain organisms become more common in the ecosystem such as the...
• 17N.3.SL.TZ0.14a: Calculate how many species are classified as endangered due to hunting and trapping.
• 17N.3.SL.TZ0.14b: State one reason mammals can continue to survive even if they are extinct in the wild.
• 17N.3.SL.TZ0.14c: Outline how deforestation can affect the richness of biodiversity in an ecosystem.
• 17N.3.SL.TZ0.14d: Explain the impact of plastic waste on Laysan albatrosses (Phoebastria immutabilis).
• 17N.3.HL.TZ0.14b.i: State the role of an indicator species.
• 17N.3.HL.TZ0.14b.ii: Identify possible approaches to maintain the population of P. sandwichensis.