2013 Notes from the Marking Centre – Biology
Introduction
This document has been produced for the teachers and candidates of the Stage 6 Biology course. It contains comments on candidate responses to the 2013 Higher School Certificate examination, highlighting their strengths in particular parts of the examination and indicating where candidates need to improve.
This document should be read along with:
- the Biology Stage 6 Syllabus
- the 2013 Higher School Certificate Biology examination
- the marking guidelines
- advice for candidates attempting science examinations
- Advice for HSC students about examinations
- other support documents developed by the Board of Studies, Teaching and Educational Standards NSW to assist in the teaching and learning of Biology in Stage 6.
Section I – Part B
Candidates showed strength in these areas:
- identifying T-cells (Q.21)
- knowledge of Morgan’s contribution to the understanding of sex linkage (Q.22)
- explaining the adaptations of spinifex to prevent water loss (Q.23)
- understanding Pasteur’s swan neck flask experiment (Q.24a)
- recognising the conditions responsible for enzyme denaturation (Q.25c)
- explaining changes in populations using Darwin/Wallace Theory of Evolution (Q.26)
- using a case study to account for increasing resistance to a once deadly virus (Q.26)
- knowledge of advances in reproductive technologies (Q.30)
- explaining how the process of filtration and reabsorption in identified areas of the nephron regulate urine composition (Q.29c)
- knowledge of methods to manage animal diseases (Q.28b)
- understanding that there has been a shift in emphasis from treatment to prevention when managing disease (Q.28b).
Candidates need to improve in these areas:
- knowledge of the specific roles of T-cells, particularly Cytotoxic T-cells (Q.21)
- explaining Morgan’s non-Mendelian ratios (Q.22)
- using experimental controls and differentiating experimental validity, reliability and accuracy (Q.24b)
- interpreting graph gradients (Q.25b)
- knowledge of methods to manage plant diseases (Q.28b)
- understanding the role of the hormones aldosterone and ADH in the formation of urine (Q.29)
- demonstrating the link between chromosomal structure and inheritance (Q.30).
Section II – Options
Question 31 – Communication
Candidates showed strength in these areas:
- knowledge of vocal cord structure and its role in sound production (part a)
- outlining the hearing pathway and transfer of mechanical energy (part b)
- understanding the process of accommodation (part c)
- outlining the function of cones and distribution of photoreceptors (part d)
- recognising advantages and limitations of hearing technologies (part e).
Candidates need to improve in these areas:
- making the connection between changes in lens shape to focusing of near and distant objects onto the retina/fovea (part c).
Question 32 – Biotechnology
Candidates showed strength in these areas:
- outlining the function of RNA (part a)
- knowledge of domestication and relevant ethical issues of current biotechnologies (part e).
Candidates need to improve in these areas:
- knowledge of traditional methods of fermentation (part b).
Question 33 – Genetics: The Code Broken?
Candidates showed strength in these areas:
- defining, outlining and providing examples of polygenic inheritance (part a)
- constructing di-hybrid cross Punnett squares (part c)
- knowledge of the Human Genome Project and gene therapy (part e).
Candidates need to improve in these areas:
- outlining the steps involved in protein synthesis (part b)
- interpreting the relationship between Mendel’s experimental results and gene linkage (part c)
- knowledge of the mechanisms of genetic change (part d)
- explaining the link and differences between gene therapy and the Human Genome Project (part e).
Question 34 – The Human Story
Candidates showed strength in these areas:
- knowledge of modern techniques of molecular analysis and features used to classify Homo sapiens (part a)
- knowledge of cultural development of humans (part d)
- knowledge of hominid skeletons (part e).
Candidates need to improve in these areas:
- interpreting trends from data in tables (part c)
- applying evolutionary knowledge to cultural development (part d).
Question 35 – Biochemistry
Candidates showed strength in these areas:
- interpreting data in graphs (part c)
- identifying the products of photosynthesis (part e).
Candidates need to improve in these areas:
- recognising light reaction mechanisms and pathways (parts a and c)
- knowledge of experiments performed by Emerson, Arnold, Gaffron and Wohl (part c)
- understanding the use of isotopes in determining biochemical pathways (part d)
- explaining how photosynthesis could assist in solving environmental issues (part e).