Question

Check all strategies below that helped you decrease experimental error in this lab.

using seeds from the same source

using the same kind of soil for both groups

giving the control and experimental groups the same volume of water

keeping the light the same for the experimental and control groups

measuring plant height the same way and at the same time for both groups

Answer 1

All five strategies help reduce experimental error:

- using seeds from the same source — reduces genetic variability between plants
- using the same kind of soil for both groups — keeps nutrient/texture differences from affecting results
- giving the control and experimental groups the same volume of water — prevents water amount from confounding the treatment effect
- keeping the light the same for the experimental and control groups — controls for differences in growth due to light
- measuring plant height the same way and at the same time for both groups — reduces measurement bias and timing-related variation