Experimentation P.1

Question 1

What is a pilot study?

Answer 1

Short experiment that are commonly carried out before starting a scientific investigation

Question 2

What is the purpose of a pilot study?

Answer 2

To develop and improve experimental protocols, ensuring the experimental design is suitable for investigation

Question 3

Give advantages of pilot studies (3)

Answer 3

1. Allows a new protocol to be developed
2. Ensures an appropriate range of values for the independent variable
3. Allows practice of an established protocol

Question 4

What are the three type of variables?

Answer 4

Independent, Dependent, Confounding

Question 5

What is an independent variable?

Answer 5

An independent variable is the variable that is changed in a scientific experiment.(x-axis variable)

Question 6

What is a dependent variable?

Answer 6

A dependent variable is the variable being measured in a scientific experiment. (y-axis variable)

Question 7

What is a confounding variable?

Answer 7

Variable, other than the independent variable that may affect the dependent variable

Question 8

What is used if confounding variables cannot be controlled effectively?

Answer 8

Randomised Block Design

Question 9

What type of sampling is Randomised Block Design?

Answer 9

Stratified Sampling

Question 10

What are the two classes of variables?

Answer 10

1. Discrete (falling into distinct groups).

2. Continuous (having a range of values)

Question 11

Give 2 examples of qualitative data (i.e characteristics or qualities)

Answer 11

1. Emotions

2. Colour of leaf

Question 12

How is qualitative (characteristics/qualities) data presented?

Answer 12

Bar graph

Question 13

What is a multi factorial experiment?

Answer 13

Experiments that combine more than one independent variable or treatment

Question 14

What is an Advantage and disadvantage of multifactorial experiment (3)

Answer 14

1. More generalisable than simple experiments because it’s using several different independent factors
2. Results are more applicable to an in vivo situation.
3. But they are more complex to perform and analyse

Question 15

What is an Advantage and disadvantage of simple experiment (2)

Answer 15

1. they are straightforward to perform (due to the ease of controlling laboratory conditions)
2. but their results may not be applicable to an in vivo situation.

Question 16

What is Precision?

Answer 16

Precision measures how closely grouped the measured values are to each other

Question 17

How is Validity achieved?

Answer 17

by having variables controlled so that any measured effect is likely to be due to the independent variable.

Question 18

How is reliability achieved?

Answer 18

By having consistent values in repeats and independent replicates.

Question 19

What is a hypertonic solution?

Answer 19

A solution that contains more dissolved particles (such as salt and other electrolytes) than is found in normal cells and blood.

Question 20

What is a hypotonic solution?

Answer 20

A solution that contains fewer dissolved particles (such as salt and other electrolytes) than is found in normal cells and blood.

Question 21

What is isotonic solution?

Answer 21

A solution that contains same concentration of dissolved particles (such as salt and other electrolytes) as found in normal cells and blood

Question 22

What are the types of sampling?

Answer 22

1. Systematic
2. Stratified
3. Random

Question 23

What is systematic sampling?

Answer 23

Members of pollution selected at regular intervals

Question 24

What is random sampling?

Answer 24

Members of population having equal chance of being selected

Question 25

What is stratified sampling?

Answer 25

Population divided into categories and sampled proportionally

Question 26

What is in vitro experiment?

Answer 26

Carried out using isolated parts of an organism in the lab.

Question 27

What is in vivo experiment?

Answer 27

Carried out within whole living organism.

Question 28

Advantage and disadvantage of in vivo?

Answer 28

While in vivo are more realistic of natural conditions they are less easy to control/replicate