IB ESS SL 1.2 Systems Question Bank

[Maximum number: 20]

(a)

Outline how four different factors influence the resilience of an ecosystem.

[ 4 ]

(b)

Explain how a community of trees in a woodland may be considered a system.

[ 7 ]

(c)

Disturbance of the composition and processes of the atmospheric system through human activity always disturbs the equilibria of marine systems.

Discuss the validity of this statement with reference to named examples.

[ 9 ]

• understanding concepts & terminology of greenhouse gases; global warming; thermal expansion; rising sea-level; melting ice caps; salinity; ocean acidification; ozone depletion; UV radiation; global productivity; tropospheric ozone; acid rain (worth noting here that acid rain is NOT a significant cause/contributor to ocean acidification); etc
• breadth in addressing and linking impacts on atmospheric systems (increased $\mathrm{CO}_{2}$ ; global warming; ozone depletion; tropospheric ozone; acid rain; etc) with disturbances in marine systems (rising sea level; ocean currents; fish migration; acidification; destruction of coral reefs; phytoplankton / marine food chains; etc)
• examples of relevant atmospheric pollutants/disturbances; ocean currents; coral communities; migratory fish; marine food chains; etc
• balanced analysis of the extent to which each atmospheric disturbance causes disturbance in marine systems whether significant, minimal or none at all, acknowledging relevant counter-arguments/alternative viewpoints;
• a conclusion that is consistent with, and supported by analysis and examples given e.g. generally, the statement is valid regarding large scale disturbances to the atmosphere such as global warming and ozone depletion but more localized disturbances like tropospheric ozone and acid rain have fairly minimal impact;

The following guide for using the markbands suggests certain features that may be offered in responses. The five headings coincide with the criteria given in each of the markbands (although "ESS terminology" has been conflated with "Understanding concepts"). This guide simply provides some possible inclusions and should not be seen as requisite or comprehensive. It outlines the kind of elements to look for when deciding on the appropriate markband and the specific mark within that band.

NB This is only an example of a possible conclusion. Candidates' conclusions do not have to agree.
Use the official Section B, part (c) markbands below.

Marks	Level descriptor
0	The response does not reach a standard described by the descriptors below and is not relevant to the question.
1–3	The response contains: • minimal evidence of knowledge and understanding of ESS issues or concepts • fragmented knowledge statements poorly linked to the context of the question • some appropriate use of ESS terminology • no examples where required, or examples with insufficient explanation/relevance • superficial analysis that amounts to no more than a list of facts/ideas • judgments/conclusions that are vague or not supported by evidence/argument.
4–6	The response contains: • some evidence of sound knowledge and understanding of ESS issues and concepts • knowledge statements effectively linked to the context of the question • largely appropriate use of ESS terminology • some use of relevant examples where required, but with limited explanation • clear analysis that shows a degree of balance • some clear judgments/conclusions, supported by limited evidence/arguments.
7–9	The response contains: • substantial evidence of sound knowledge and understanding of ESS issues and concepts • a wide breadth of knowledge statements effectively linked with each other, and to the context of the question • consistently appropriate and precise use of ESS terminology • effective use of pertinent, well-explained examples, where required, showing some originality • thorough, well-balanced, insightful analysis • explicit judgments/conclusions that are well-supported by evidence/arguments and that include some critical reflection.

Section B, part (c) markbands (official markscheme p16)

[Maximum number: 4]

(a)

The soil system includes storages of inorganic nutrients.

[ 4 ]

(i)

Identify two inputs to these storages.

[ 2 ]

(ii)

Identify two outputs from these storages.

[ 2 ]

[Maximum number: 4]

Draw a system diagram to illustrate the impact of acid deposition on an ecosystem.

IB ESS SL 1.2 Systems Questions

Exam points

Covered syllabus points

Covered syllabus points

Question 1

Question (a)

Question (b)

Question (c)

Question 2

Question (a)

Question (i)

Question (ii)

Question 3