Scientific Skills and Bioethics

Question 1

Define accuracy and precision

Answer 1

• Accuracy refers to how close an experimental measurement is to the known or true value
  
  • Bull’s eye on a target
• Precision refers to how close multiple measurements of the same investigation are to each other
  
  • Arrows concentrated in a certain area

TIP TO REMEMBER: Accurate data is close to the actual value. Precise data is when multiple measurements are close together. (AA and PC).

Question 2

Define repeatability and reproducibility

Answer 2

• Repeatability refers to how close measurements are to each other in identical conditions
  
  • The observer repeating the experiment and producing the same results
• Reproducibility refers to how close results are when the same variable is being measured under different conditions
  
  • Other people repeating the experiment and producing the same results

NOTE: Precision can be determined by an experiment’s repeatability and reproducibility. An experiment with high precision, repeatability and reproducibility is considered reliable.

Question 3

Define validity

Internal and external

Answer 3

• Internal validity refers to how successfully an experiment measures what it was intended to measure
• External validity refers to the extent to which research findings can be generalised to a greater population

Question 4

Provide examples of potential limitations in experiments

Answer 4

• No access to specific equipment (e.g. not having a micropipette to collect accurate measurements)
• Inability to control variables (e.g. room temperature and humidity)
• Inability to repeat experiments to determine repeatability and reproducibility

Question 5

Define personal errors

Mistakes

Answer 5

• Personal errors involve mistakes or miscalculations made by the observer
• E.g. misreading numbers on a scale

Question 6

Explain random errors

Answer 6

• Random errors are unpredictable (chance) variations in measurements that affect the precision of an experiment
• Can be caused sudden environmental changes or unreliable measuring instruments
• The effect of random errors can be reduced by taking multiple measurements or increasing sample sizes

Question 7

Explain systematic errors

Answer 7

• Systematic errors affect the accuracy of a measurement and cannot be improved by repeating an experiment
• They are usually due to equipment or system errors
• Can be reduced by using equipment carefully, calibrating equipment before use and reviewing the experimental method

Question 8

List and define the different experimental variables

Answer 8

• The independent variable is the variable that is changed or manipulated
• The dependent variable is the variable that is influenced by the independent variable and is measured
• Control variables are variables that are kept constant during the entire experiment (helps ensure that results are caused solely by changes in the IV)

Question 9

Define the three ethical approaches

Answer 9

• The consequence-based approach involves maximising positive outcomes while minimising negative outcomes
• The rule-based approach involves following ethical rules, regardless of its potential consequences or outcomes
• The virtues-based approach involves making decisions based on one’s own moral compass (e.g. being honest is inherently good, regardless of whether it causes you to break a rule or cause harm)

NOTE: The consequence-based approach is often characterised by the saying “the end justifies the means.”

Question 10

Explain integrity

Answer 10

• Integrity refers to a commitment to honesty, ethical conduct, and accountability in all aspects of practice, research, and decision-making
• It involves the honest reporting of all sources of information and communication of results, whether favourable or unfavourable in ways that permit scrutiny and contribute to public knowledge and understanding

Question 11

Define justice

Answer 11

• Justice refers to the fair distribution and access to the benefits of an action
• Moral obligation to ensure that there is fair consideration of competing claims
• No unfair burden on a particular group from an action

Question 12

Define beneficence

Answer 12

• Beneficence refers to the commitment to maximising benefits and minimising risks and harms involved in a particular course of action

Question 13

Define non-maleficence

Answer 13

• Non-maleficence refers to the commitment to minimising harm, even (sometimes) at the cost of restricting people’s freedom

Question 14

Define respect

Answer 14

• Respect refers to recognizing and honoring the autonomy and rights of individuals, particularly in healthcare and research, by involving them in decision-making and treating them with dignity and fairness

Question 15

Outline the purpose of positive and negative controls

Answer 15

• Positive control is a group that is exposed to experimental treatment that produces a known result
  
  • Used to confirm that the system is functioning correctly
• Negative control is a group that is not exposed to the experimental treatment
  
  • Provides a baseline for comparison
  • Used to identify and eliminate extraneous variables

Question 16

Structure of data analysis questions

Answer 16

• Analysis requires the selection of aspects of the data and explaining their implications
• 1 mark is given for each aspect of the data being analysed (make separate points for each mark)
• Can talk about..
  
  • The precision of the results due to minimal difference in measurements between trials
  • All results showing an increase/decrease in the dependent variable regardless of change in the independent variable
    
    • E.g. All results show an increase in temperature, which indicates that the yeast was respiring in all flasks regardless of the type of sugar/sugar substitute.
  • The trial that produced the most significant change (explaining what this indicates)
    
    • E.g. Glucose produced the biggest temperature changes, meaning that the yeast produced the most amount of heat when exposed to glucose. Thus, glucose caused a higher respiration rate and was metabolised more effectively than the other sugars/sugar substitutes.
  • The trial that produced the least significant change (explaining what this indicates)