1. Home
  2. HSC
  3. HSC Exams
  4. 2010 HSC Exam papers
  5. 2010 HSC Notes from the Marking Centre — Earth and Environmental Science
Print this page Reduce font size Increase font size

2010 HSC Notes from the Marking Centre — Earth and Environmental Science

Contents

Introduction

This document has been produced for the teachers and candidates of the Stage 6 course in Earth and Environmental Science. It contains comments on candidate responses to the 2010 Higher School Certificate examination, indicating the quality of the responses and highlighting their relative strengths and weaknesses.

This document should be read along with the relevant syllabus, the 2010 Higher School Certificate examination, the marking guidelines and other support documents which have been developed by the Board of Studies to assist in the teaching and learning of Earth and Environmental Science.

General comments

Teachers and candidates should be aware that examiners may ask questions that address the syllabus outcomes in a manner that requires candidates to respond by integrating their knowledge, understanding and skills developed through studying the course, including the prescribed focused areas. It is important to understand that the Preliminary course is assumed knowledge for the HSC course.

Candidates need to be aware that the marks allocated to the question and the answer space (where this is provided on the examination paper), are guides to the length of the required response. A longer response will not in itself lead to higher marks. Writing in excess of the space allocated may reduce the time available for answering other questions.

Candidates need to be familiar with the Board’s Glossary of Key Words which contains some terms commonly used in examination questions. However, candidates should also be aware that not all questions will start with or contain one of the key words from the glossary. Questions such as ‘how?’, ‘why?’ or ‘to what extent?’ may be asked, or verbs may be used which are not included in the glossary, such as ‘design’, ‘translate’ or ‘list’.

Teachers and candidates should also be aware that questions may be asked that focus on the mandatory skills content in Module 9.1.

Candidates should use examination time to analyse the question and plan responses carefully, working within that framework to produce clear and concise responses. This may include the use of dot points, diagrams and/or tables, and avoids internal contradictions. This is particularly so in holistic questions which need to be logical and well structured.

In the best responses, candidates:

  • showed all working where required by the question
  • did not repeat the question as part of the response
  • used appropriate equipment; for example, pencils and a ruler to draw diagrams and graphs. (A clear plastic ruler would aid candidates to plot points that are further from the axes and rule straight lines of best fit.)

In Section II, the option question is divided into a number of parts. Candidates should clearly label each part of the question when writing in their answer booklets.

Candidates are reminded to attempt one question only in Section II. Candidates are also strongly advised to answer the option they have studied in class.

Section I – Core

Part B

Question 21

  1. Better responses clearly described the characteristics and features of the two physical hazards.
  2. Weaker responses simply named two features of volcanic regions that benefit agriculture.

Question 22

  1. In better responses, candidates identified the conservative boundary and clearly and concisely indicated the relative motion, including the direction in which the plates moved.

    Weaker responses confused the type of plate boundary at Y with convergent or divergent.

  2. In the best responses, candidates drew cross-sections with the subducting plate in the correct orientation with oceanic crust and continental crust differentiated by their thickness. The diagrams included labelled features drawn in the correct position with arrows clearly indicating the direction of movement.

    In weaker responses, candidates had subduction in the wrong direction, significant features in the wrong position, labels missing, or the direction of plate movement was not indicated.

  3. In better responses, candidates made a clear distinction between the two boundaries based on the presence or absence of a magma-forming process, such as partial melting as a result of subduction. These responses also included a clear connection between subduction and the presence of volcanoes.

    In weaker responses, candidates confused the nature of the boundaries or described only one boundary.

Question 23

  1. In better responses, candidates detailed differences between relative and absolute dating techniques and then related each method to dating the trilobite species.

    In weaker responses, candidates outlined the difference between relative and absolute dating techniques but could not relate each method to dating the trilobite species.

Question 24

Most candidates were able to draw a flow chart, but some lacked detail.

Question 25

    1. Although most candidates identified a valid rehabilitation strategy, some did not outline the effect of the strategy on soil salinity.
    1. In the best responses, candidates used correct scientific terminology in their responses.

Question 26

  1. In better responses, candidates provided specific detail in naming the hypotheses and referred to scientifically valid hypotheses. In weaker responses, candidates confused the extinction of the megafauna as an example of a mass extinction.
  2. In better responses, candidates described the evidence on which the hypothesis was based and made a clear judgement in their assessment. In the best responses, candidates described and assessed evidence that supported the hypothesis but also evidence that might be interpreted differently.
  3. In the better responses, candidates made their understanding of natural selection and speciation clear. They also clearly related the rapid changes in species to changed environmental conditions. A common feature of weaker responses was the implication that the changed environment gave rise to the variation needed for evolution to occur.

Question 27

In better responses, candidates addressed the need to design an investigation, not just a practical method to test one effect. They mentioned some means of calibrating the level of compaction and included testing for more than one effect, and compared results.

In weaker responses, candidates failed to use independent and dependent variables such as compaction and lack of compaction, or control the amount of water used, how plants were treated etc. They did not explain how they were measuring such things as erosion and plant growth.

Question 28

In stronger responses, candidates clearly identified the process involved and then fully outlined three or more causes.

In weaker responses, candidates had difficulty giving three full outlines, although most were able to identify the three processes.

Question 29

In stronger responses, candidates identified the process of bio-magnification/bio-accumulation and identified one or two impacts that the pesticide could have on the estuary food chain shown, or accurately described the flow-on effects of losing an organism on the other organisms present.

In weaker responses, candidates did not relate the impacts given to the river estuary food chain or did not identify the type of effect.

Question 30

In stronger responses, candidates gave good descriptions of geological processes and human activity since the Industrial Revolution, and included an analysis of the relative effect of each process on the climate. Weaker responses failed to analyse the processes.

Section II – Options

Question 31 – Introduced species and the Australian environment

  1. Better responses provided sufficient detail of the chosen methods.

    Weaker responses either lacked sufficient detail or the methods chosen were either not appropriate or too general. Some responses evaluated the methods rather than described them.

    1. In better responses, candidates referred to the specific time frame and identified the general trend of the Tasmanian Devil declining. In weaker responses, candidates did not link trends to specific time frames.
    1. In better responses, candidates identified a direct correlation between the rise in the population of the introduced species and the decline in the population of the Tasmanian Devil. They also provided a plausible cause and effect for the relationship.

      In weaker responses, candidates did not link trends to specific time frames. They also did not adequately explain how the population of the introduced species increased dramatically during the time frame given.

  1. In better responses, candidates clearly described the Bradley method by stating the principles behind its design. They often described methods used to both remove the introduced species and encourage the regeneration of the native species.

    In better responses, candidates demonstrated a clear understanding of what a hypothesis might be when they identified the relationship between the two variables.

    1. In weaker responses, candidates either did not identify the relationship between the variables in the data so did not draw a valid hypothesis, or did not understand the term hypothesis.
    1. In better responses, candidates demonstrated a clear understanding of how to construct a first-hand investigation, with reliability ensured via controlling variables not tested, repetition and the use of a control. They clearly linked the hypothesis to the method and recognised the independent and dependent variables.

      In weaker responses, candidates did not outline methods that would ensure reliability and accuracy of the results via repetition, use of a control or controlling variables. They also did not describe the type of data to be collected.

  1. In better responses, candidates named the successful control method as biological control via the cactoblastis moth and clearly indicated the main features of this method.

    In weaker responses, candidates only gave general features of biological control or named the moth but did not indicate the main features of the method.

  2. In better responses, candidates made a definitive judgement clearly linked to criteria, which were described and explained in detail. They displayed an understanding of what defines an introduced species and used at least two examples of organisms considered as introduced, explaining their impacts on the biotic and abiotic factors of the Australian environment. They then linked the interaction of these factors to display an understanding of the multidimensional effects of the impacts to the peculiar nature of the Australian environment.

    In weaker responses, candidates named two or more species which were regarded as introduced and explained the impacts of both on some of the general biotic/abiotic factors of the environment. No clear judgements were made regarding the impacts explained and multi-dimensional aspects of impacts were lacking.

    In the weakest responses, candidates named one or two introduced species, outlined the history of their introduction, reasons for their success as a species and described their impacts in general terms with little recognition of the interaction with and between factors of the Australian environment.

20110101

Print this page Reduce font size Increase font size