Core Practicals Flashcards
Light intensity and photosynthesis
Add 20 Algo balls to each glass bottle
Add same amount of indicated to each bottle and put on lids (usually hydrogen carbonate which creates carbon dioxide so it can photosynthesise)
Record the start pH of each bottle
Set up tank of water between the bottles and light source (to absorb more heat so it’s that same temp as enzymes control by temp)
Put tinfoil around one bottle to keep in dark
Turn lights on and leave for a period of time
Record PH of each bottle at the end of the experiment
Have the same number of angles, same volume and same concentration
Respiration rates
Add Soda lime to boiling tube, add cotton wall(Soda lime absorbs carbon dioxide)
Gently add some organisms to tube
Insert bung and delivery tube (to seal it to ensure no gas leaves or enters)
Set up a controlled tube
Add both tubes to water and wait five mins for organisms to adjust to temp
Whole beaker of colour liquid to delivery tube and mark the start position of the ink
Time for five minutes, Mark new position of liquid and record distance moved ( pressure decreases as respiration takes place as oxygen is taken in)– repeat a different temps
As temp increases distance increases due to an increase in kinetic energy of the enzyme
Quadrats and transects
Peg out tape measure on ground starting where there is no shade to where there is heavy shade
Mark out regular intervals on tape measure
Place top left corner of quadrat at first point on transect
Record the abiotic factors
Record numbers of plants at that point and repeat at each point on transect
As you get further away from shade, plants increase due to reduction in competition
