HSC Exam Practice

Sample response. Biotechnology is the use of living organisms, cells or biological processes to make products or solve problems. It is applied in agriculture, medicine and industry and includes both traditional and modern practices.

Marking notes. 1 mark for identifying biotechnology as the use of living organisms / cells / biological processes; 1 mark for naming sectors (agriculture, medicine, industry) or for including both traditional and modern scope.

Sample response. Traditional biotechnology uses biological systems without direct genetic analysis or manipulation, for example fermentation and selective breeding. Modern biotechnology uses techniques that analyse, transfer or alter DNA directly, such as recombinant DNA technology, cloning and gene editing. The defining difference is the level of direct molecular control over genetic material.

Marking notes. 1 mark for characterising traditional biotechnology (biological systems without direct DNA manipulation); 1 mark for characterising modern biotechnology (direct DNA analysis / manipulation); 1 mark for naming the distinguishing feature (direct genetic manipulation).

Sample response. Traditional: (i) brewing beer using yeast fermentation; (ii) selective breeding of Merino sheep for wool quality. Modern: (i) production of human insulin in engineered E. coli using recombinant DNA technology; (ii) CRISPR-Cas9 gene editing of crops to introduce disease resistance.

Marking notes. 1 mark per correctly named traditional example (max 2); 1 mark per correctly named modern example with named tool (max 2). A modern example without a named tool scores 0.

Sample response. Insulin production began as a traditional biotechnology in the 1920s, with insulin extracted from cattle and pig pancreases. From 1982, recombinant DNA technology was used to produce human insulin in engineered E. coli, giving a structurally identical product at scale. Insulin therefore demonstrates the same biological need (treating diabetes) being met by both traditional and modern biotechnology, making it a clear bridge example.

Marking notes. 1 mark for identifying the traditional (animal-derived) pipeline; 1 mark for identifying the modern (recombinant) pipeline; 1 mark for explicitly linking the case to the traditional–modern trajectory.

Sample response. A definition restricted to gene editing would exclude fermentation, selective breeding, domestication, recombinant production of medicines and many industrial processes — in fact most of biotechnology by both history and revenue. Biodiversity discussions would therefore omit the millennia-long impact of domestication and crop selection on global agricultural biodiversity. Ethical evaluation would also be skewed, because the public’s real exposure to biotechnology (bread, beer, livestock breeding, vaccines) would be invisible to the evaluator.

Marking notes. 1 mark for identifying that the narrow definition excludes most of the field; 1 mark for biodiversity-specific reason (e.g. domestication / crop selection / monoculture impact); 1 mark for ethics-specific reason (e.g. real public exposure to traditional biotechnology).

Sample response. Agriculture — selective breeding of livestock or engineered Bt cotton. Medicine — recombinant insulin production in E. coli. Industry — production of industrial enzymes (e.g. detergent proteases) using engineered microorganisms.

Marking notes. 1 mark per correctly named sector with a valid biotechnology example (3 × 1).

Sample response (a). Biotechnology revenue is highly uneven across sectors. Medical biotechnology dominates the market at ~520 USD bn, more than four times the size of the next largest sector (agriculture, ~125 USD bn). Industrial biotechnology (~95 USD bn) and environmental biotechnology (~38 USD bn) make up the middle tier, while marine biotechnology is the smallest sector at only ~6 USD bn. The distribution is strongly right-skewed, with one dominant sector and a long tail of smaller ones.

Sample response (b). Total = 520 + 125 + 95 + 38 + 6 = 784 USD bn. Medical share = 520 ÷ 784 ≈ 66%. The medical sector is so much larger than the agricultural sector primarily because modern biotechnology generates very high-value products there: recombinant biopharmaceuticals (insulin, clotting factors), monoclonal antibodies, mRNA vaccines and gene therapies all command high prices and treat large global patient populations. Agricultural biotechnology produces commodity outputs (grain, fibre, livestock) with lower per-unit margins, even though selective breeding and engineered crops are widely used. The two sectors differ in revenue not because one is more biotechnological than the other, but because of the price and demand profile of their end products.

Marking notes. Part (a) — 1 mark for identifying that medical dominates; 1 mark for ranking at least three sectors with figures; 1 mark for describing the overall shape of the distribution. Part (b) — 1 mark for correct calculation (~66%); 1 mark for identifying high-value modern medical biotechnology products; 1 mark for explicitly contrasting product value / margin between medical and agricultural biotechnology rather than implying agriculture is less biotechnological.

Sample response. The claim that biotechnology is best defined as “the modern manipulation of DNA” is too narrow. Biotechnology is the use of living organisms, cells or biological processes to make products or solve problems in agriculture, medicine and industry — a definition that explicitly covers both traditional and modern practice. Restricting biotechnology to direct DNA manipulation excludes major historical and contemporary examples and distorts later evaluation. Traditional biotechnology has been practised for thousands of years: fermentation by Egyptian brewers used yeast to convert sugars into ethanol around 6000 BCE, and Neolithic farmers domesticated wheat and selectively bred livestock without any molecular knowledge of DNA. These practices still meet the syllabus definition because they deliberately direct biological systems toward human purposes. The historical trajectory then runs through nineteenth-century insights such as Pasteur’s identification of microbes in fermentation (1857) and Mendel’s laws of inheritance (1866), into the molecular era with Watson and Crick’s double-helix model (1953), and finally into the genomic era opened by Boyer and Cohen’s recombinant DNA (1973) and the FDA approval of recombinant Humulin insulin in 1982. Modern biotechnology adds direct DNA analysis, transfer and editing — for example, CRISPR-Cas9 was used in 2023 to create the first approved gene-editing therapy for sickle-cell disease. Named examples confirm the breadth of the field across sectors. In medicine, recombinant human insulin produced in engineered E. coli is modern biotechnology, while plasma fractionation of clotting factors at Australia’s CSL is traditional biotechnology — both are biotechnology. In agriculture, selective breeding of Merino sheep is traditional biotechnology, while marker-assisted selection and Bt cotton are modern. The narrow claim would exclude all of these traditional examples, even though they still operate at industrial scale today and account for around a third of global biotechnology revenue. The lesson’s broad definition is therefore not just historically accurate but practically necessary: later evaluations of biodiversity (domestication shaped global crop diversity) and ethics (public exposure to biotechnology is mostly via food and medicine, not just CRISPR) only make sense when the whole field is in view. The claim should be rejected and replaced with the syllabus definition, which treats modern molecular techniques as the most recent extension of biotechnology rather than its definition.

Marking notes. 1 mark — defines biotechnology accurately (living organisms / cells / biological processes used for human purposes). 1 mark — identifies the claim as too narrow and rejects it explicitly. 1 mark — gives at least two named traditional examples (e.g. fermentation, selective breeding, domestication). 1 mark — gives at least two named modern examples with their tools (e.g. recombinant insulin / Humulin, CRISPR, marker-assisted selection). 1 mark — uses named examples from at least two different sectors (agriculture, medicine, industry). 1 mark — traces the historical trajectory from past (e.g. domestication, fermentation) to present (recombinant DNA, gene editing). 1 mark — reaches an explicit evaluative judgement and reformulates the claim using the broad syllabus definition.