Year 1 Practical Techniques Flashcards
What do you need to know about RP1 Rate of Enzyme Reaction
What do you need to know about RP2 Root Tip Squash
What do you need to know about RP3 Water Potential in Plants
What do you need to know about RP4 Membrane permeability
What do you need to know about RP5 Dissection
What do you need to know about RP6 Antibiotic Resistance
What are the benefits of a colourimeter?
It removes subjectivity in colour judgements
How do you use a colourimeter?
Use a colorimeter to determine the absorbance/transmittance of the known concentration solutions to use as a colour standard/comparison
If there is an end point of the reaction the absorbance will be a reference to the end point
What does interpolate mean?
To read one piece of data off a graph, go up/across to the line of best fit and then read off the other value
How do you reduce subjectivity when investigating a reaction with a colour change and no colourimeter is available
Set up a dilution series of known concentrations
Complete the reaction (e.g. Benedicts test)
Use a colour scale of the known concentration solutions to use as a colour standard/comparison
If there is an end point of the colour scale will be a reference to the end point
What are the most common control variables in experiments
Concentration
Volume
pH
Temperature
Number/Mass of organism uses
Species of organism used
What is the difference between a control variable and a control experiment?
Control variables are held constant or measured throughout a study for both control and experimental groups.
Control groups do not undergo the experimental treatment of interest and their outcomes are compared with those of the experimental group.
What is the independent variable?
Independent variables are the variables you change in the hopes of observing an effect
What is the dependent variable?
Dependent variables vary are the one you measure
How should you write a null hypothesis
There is no effect of the ‘independent variable’ on the ‘dependent variable’
