Reaction Time Practical
1
Preparations
- Get a partner.
- Person 2 should sit on a chair, and place the forearm of their non-dominant arm on a table with their non-dominant hand hanging off the table's edge.
- Person 1 should hold a ruler directly over Person 2's hand, ensuring that 0cm lines up with the tippedy top of Person 2's hand.
2
Testing
- Person 1 should drop the ruler randomly without giving any indication to person. Person 2 should catch the ruler as quickly as they possibly can, by clentching their fist.
- Record the number from the ruler that is in line with the top of Person 2's thumb.
- Repeat steps 1 - 2 five times.
- Each person should swap roles and repeat steps 1 - 2.
- Use a conversion table to convert the recorded distances into reaction times.
Plant Responses Practical
1
Germination
- Pour a fixed volume of water into three petri dishes.
- Place cotton wool in the petri dishes.
- Place 10 seeds in each petri dish.
- Leave the petri dish in a warm location and allow time for the seeds to germinate.
Safety Concerns
- Seeds may be a biohazard. Wash hands after handling seeds.
2
Altering Light Intensity - Once the seeds have germinated, make sure that there is an equal number of seeds in each petri dish, if not all seeds have germinated, remove the ungerminated seeds. If this causes an imbalance in the number of seeds in each petri dish, remove seeds from other petri dishes until each petri dish has the exact same amount of seeds.
- Place each petri dish in a different environment: One in sunlight (eg: windowsill); one in partial sunlight; and one in complete darkness (eg: a cupboard).
- Everyday for five days, measure the height of each seedling in each petri dish with a ruler, ensuring that they are at full height (Use forcepts to fully extend the seedlings), and record the results.
- Calculate the mean height of the seedlings in each petri dish each day.