Unit 3

Question 1

Replacement

Answer 1

The use of animals should be replaced with alternatives as often as possible

Question 2

Reduction

Answer 2

The number of animals used in a study should be reduced as much as possible.

Question 3

Refinement

Answer 3

For those animals being used, the negative impact on them should be minimised.

Question 4

Validity

Answer 4

Variables are CONTROLLED, so that any measured effect is likely to be due to the independent variable.

Question 5

Reliability

Answer 5

Consistent values in repeats and replicates

Question 6

Accuracy

Answer 6

Data, or means of data sets, are close to the true value

Question 7

Precision

Answer 7

Measured values are close to each other. The results show little variation.

Question 8

Independent variable

Answer 8

The variable that is being changed in a scientific experiment.

Question 9

Dependent variable

Answer 9

The variable being measured in a scientific experiment.

Question 10

Discrete

Answer 10

Finite values that allow placement into separate groups.

Question 11

Continuous

Answer 11

Values change gradually from one extreme to another.

Question 12

Confounding variable

Answer 12

A confounding variable is a variable, other than the independent variable, that may affect the values of the dependent variable.

Question 13

Negative control

Answer 13

Provides results for what happens in the absence of a treatment.
(i.e. doesn’t include the independent variable)

Question 14

Positive control

Answer 14

A positive control is included to check that the system can detect a positive result when it occurs.

Question 15

Placebo effect

Answer 15

The placebo effect is a measurable change in the dependent variable, as a result of the PATIENTS EXPECTATIONS, rather than changes in the independent variable.

Question 16

In Vitro

Answer 16

In vitro refers to the technique of performing a given procedure in a controlled environment OUTSIDE of a living organism.

E.g. cells growing in a culture medium

Question 17

In Vivo

Answer 17

In vivo, refers to experimentation using a whole, living organism.

Question 18

Random sampling

Answer 18

In random sampling, members of a population have an equal chance of being selected.

Question 19

Systematic sampling

Answer 19

In systematic sampling, members of a population are selected at regular intervals.

Question 20

Stratified sampling

Answer 20

In stratified sampling, the population is divided into categories that are sampled proportionally.

Question 21

Representative sample

Answer 21

A representative sample should share the same mean and the same degree of variation about the mean as the population as a whole.

Question 22

Qualitative data

Answer 22

Subjective and descriptive

Difficult to analyse, and difficult to measure directly

Question 23

Quantitative data

Answer 23

Measured objectively, usually with a numerical value
Measured directly

Question 24

Ranked data

Answer 24

Data is sorted in order of magnitude
E.g. data is sorted from low to high

Question 25

Correlation

Answer 25

Correlation exists if there is a relationship between 2 variables.

Question 26

Positive correlation

Answer 26

When one variable increases, then the other variable increases too

Question 27

Negative correlation

Answer 27

When an increase in one variable is accompanied by a decrease to the other.

Question 28

Review Articles

Answer 28

Summarise current knowledge and recent findings in a particular field

Question 29

Peer Review

Answer 29

Where specialists with expertise in the relevant field asses the scientific quality of a submitted manuscript and make recommendations regarding its suitability for publication.

Question 30

Ethics in human studies

Answer 30

Informed consent The right to withdraw data Confidentiality

Question 31

Pilot study

Answer 31

Used to help plan procedures, asses validity and check techniques

Question 32

Randomised block design

Answer 32

Where confounding variables cannot be controlled, a randomised block design could be used.