Respirometer Practical Flashcards
How do you measure the rate at which an organism is doing respiration?
With a respirometer
What is the independent variable in the respirometer practical?
Temperature (it changes)
What is the dependent variable in the respirometer practical?
Distance travelled by liquid / rate of reaction (what you measure)
What are the control variables in the respirometer practical?
Volume of sodium hydroxide, mass of organism, volume of coloured liquid (what you keep the same)
What is the independent variable in the practical?
Temperature
What is the dependent variable?
Distance travelled by liquid (rate of reaction)
What are the control variables in the practical?
Volume of sodium hydroxide, mass of animal, volume of coloured liquid
What equipment is used in the respirometer practical?
Sodium hydroxide or soda lime (absorbs CO2), filter paper, insect, gauze, syringe, closed tap, manometer (U-tube containing coloured liquid)
Why are the glass beads important?
They act as a control
What is the role of the syringe?
Resets liquid position
What will happen in this practical?
The amount of O2 will decrease over time, and the liquid will move further towards the insect - the rate of respiration is distance moved by liquid / time
What does a respirometer measure?
How fast an organism is doing respiration
