1.2 Key science skills

1.2

Key science skills

KEY IDEAS

In this topic, you will learn that: ✚ the key science skills are important to succeeding in VCE Biology. Study tip The key science skills are central to the VCE Biology course, When formulating across Units 1–4 and over all Areas of Study. They will be hypotheses, consider essential when you undertake investigations and evaluate the relationship research. between the independent and These science skills are important for planning dependent variables, and conducting practical investigations, collating and and make sure the possible outcome is analysing primary and secondary data, organising formed from accurate data in an informed manner, identifying errors and scientific knowledge. uncertainty, critically evaluating methodology, and researching and communicating scientific ideas. Practising the key science skills is important for succeeding in your assessments, and opportunities for this are available throughout this course.

independent variable

the variable that is changed or controlled in an experiment

dependent variable

the variable being tested and measured in an experiment

controlled variable

a variable that is kept constant in an experiment

hypothesis

a prediction of the outcome of a practical investigation based on accurate scientific knowledge

risk assessment

a document that outlines the potential risks, hazards and subsequent control measures that should be taken to avoid harm FIGURE 1 You need to determine how you are going to conduct your investigation and what kind of data you will measure.

Understanding the key science skills

There are seven main key science skills, which you should consider when conducting practical investigations and evaluating research. These are summarised in Table 1. TABLE 1 The key science skills as outlined by VCAA Key science skill VCE Biology Units 1–4 Develop aims and questions, formulate hypotheses and make predictions • identify, research and construct aims and questions for investigation • identify independent, dependent and controlled variables in controlled experiments • formulate hypotheses to focus investigations • predict possible outcomes Plan and conduct investigations • determine appropriate investigation methodology: case study; classification and identification; controlled experiment; correlational study; field work; literature review; modelling; product, process or system development; simulation • design and conduct investigations; select and use methods appropriate to the investigation, including consideration of sampling technique and size, equipment and procedures, taking into account potential sources of error and uncertainty; determine the type and amount of qualitative and/or quantitative data to be generated or collated • work independently and collaboratively as appropriate and within identified research constraints, adapting or extending processes as required and recording such modifications Comply with safety and ethical guidelines

• demonstrate safe laboratory practices when planning and conducting DRAFT ONLY - NOT FOR SALE investigations using risk assessments, informed by safety data sheets (SDS), and accounting for risks • apply relevant occupational health and safety guidelines while undertaking practical investigations • demonstrate ethical conduct when undertaking and reporting investigations

Key science skill VCE Biology Units 1–4

Generate, collate and record data • systematically generate and record primary data, and collate secondary data, appropriate to the investigation, including use of databases and reputable online data sources • record and summarise both qualitative and quantitative data, including use of a logbook as an authentication of generated or collated data • organise and present data in useful and meaningful ways, including schematic diagrams, flow charts, tables, bar charts and line graphs • plot graphs involving two variables that show linear and non-linear relationships

Analyse and evaluate data and investigation methods • process quantitative data using appropriate mathematical relationships and units, including calculations of ratios, percentages, percentage change and mean • identify and analyse experimental data qualitatively, handling where appropriate concepts of: accuracy, precision, repeatability, reproducibility and validity of measurements; errors (random and systematic); and certainty in data, including effects of sample size in obtaining reliable data • identify outliers, contradictory or provisional data • repeat experiments to ensure findings are robust • evaluate investigation methods and possible sources of personal errors/mistakes or bias, and suggest improvements to increase accuracy and precision and to reduce the likelihood of errors

Construct evidence-based arguments and draw conclusions • distinguish between opinion, anecdote and evidence, and scientific and nonscientific ideas • evaluate data to determine the degree to which the evidence supports the aim of the investigation, and make recommendations, as appropriate, for modifying or extending the investigation • evaluate data to determine the degree to which the evidence supports or refutes the initial prediction or hypothesis • use reasoning to construct scientific arguments, and to draw and justify conclusions consistent with the evidence and relevant to the question under investigation • identify, describe and explain the limitations of conclusions, including identification of further evidence required • discuss the implications of research findings and proposals

Analyse, evaluate and communicate scientific ideas

• use appropriate biological terminology, representations and conventions, including standard abbreviations, graphing conventions and units of measurement • discuss relevant biological information, ideas, concepts, theories and models and the connections between them • analyse and explain how models and theories are used to organise and understand observed phenomena and concepts related to biology, identifying limitations of selected models/theories • critically evaluate and interpret a range of scientific and media texts (including journal articles, mass media communications and opinions in the public domain), processes, claims and conclusions related to biology by considering the quality of available evidence • analyse and evaluate bioethical issues using relevant approaches to bioethics and ethical concepts, including the influence of social, economic, legal and political factors relevant to the selected issue • use clear, coherent and concise expression to communicate to specific audiences DRAFT ONLY - NOT FOR SALE and for specific purposes in appropriate scientific genres, including scientific reports and posters • acknowledge sources of information and assistance, and use standard scientific referencing conventions Source: VCE Biology Study Design (2022–2026) reproduced by permission © VCAA

Video Writing a hypothesis

Formulating a hypothesis

When conducting scientific investigations, you will be required to develop a hypothesis. A hypothesis is developed from a research question. It is written as a testable statement that may include a prediction about the outcome of the investigation. There is not one correct way to write a hypothesis, but the following steps can be helpful to make sure you include everything you need. 1 Ask a research question. This must be specific and testable. (For example: Does mould grow faster if it is not exposed to light?) 2 Identify the independent and dependent variables in the research question. (In the above example, the rate of mould growth is the dependent variable, and the amount of light is the independent variable.) 3 Write an IF, THEN, BECAUSE statement, which provides a possible explanation for the relationship between the independent and dependent variables. IF THEN BECAUSE IF THEN BECAUSE If the independent variable is changed then the dependent variable will increase/ decrease/grow/be larger than/be smaller than etc. because of scientific reasoning. For example, if the amount of sunlight available is reduced, then the rate of mould growth increases because sunlight causes moisture to evaporate from the air, and mould needs moisture in order to grow.

Resource Risk assessments

Risk assessment A risk assessment is a systematic way of identifying hazards and risk factors that could template potentially cause harm, and then implementing control measures to avoid those risks. There are different formats to generate a risk assessment, and some programs will automatically generate the risk assessment for you. It is important that you follow the control measures outlined in the risk assessment to ensure the safety of all people involved in the practical investigation. For example, if you are using a Bunsen burner, you should identify all the possible hazards (e.g. burns) involved. You should then outline the measures you will take to reduce the risks and have a plan in place in case something goes wrong. You can find a blank risk assessment template on your Student obook pro.

Describe and explain

1 Explain the importance of complying with safety and ethical guidelines when planning and conducting practical investigations. 2 Explain why a hypothesis should be written before an experiment is conducted.

Design and discuss

3 An experiment was being conducted to investigate the effect of salinity on the movement of water by osmosis into and out of plant cells.

Four different concentrations of salt solution were prepared by mixing salt with water: 0%,

CHECK 2%, 4% and 6%. A potato was cut into cubes 1 cm × 1 cm × 1 cm. A cube was weighed and then placed into a beaker of 0% salt concentration. The mass of the potato cube was recorded after 5 minutes in the solution. This was repeated for the other salt solutions. Design a hypothesis for this investigation. 4 Design a risk assessment for the practical investigation described in Question 3. YOUR LEARNING 1.2 DRAFT ONLY - NOT FOR SALE 5 A scientist planned a controlled experiment to determine if the temperature of a bedroom affected how much a person sleeps. Suggest a possible hypothesis for this experiment.