Required practical - germinated seedlings

Question 1

Method for required practical?

Answer 1

1) Put cotton wool into three petri dishes, and add the same volume of water to each dish.
2) Add ten seeds to each dish and place them in a warm place where they won’t be disturbed.
3) Allow the seeds to germinate, and add more water if the cotton wool dries out.
4) Once the seeds have germinated, ensure the petri dishes each contain the same number of seeds, and remove any extra seeds if necessary.
5) One petri dish will sit in full light on a windowsill, the second will be in a dark cupboard, and the final dish will be placed in partial light.
6) Every day for one week, measure the height of each seedling and record the results in a table. You must record the height of the individual seedlings on each day.
7) Calculate the mean of the seedlings each day, and compare the mean heights in the three different locations.

Question 2

Dependent variable

Answer 2

Mean height of the seedlings

Question 3

Control variables

Answer 3

number of seeds on each dish, how much they are spread out, the volume of water the seedlings are given, the temperature they are kept at

Question 4

Independent variables

Answer 4

place plants in light and dark conditions. Other suitable different colours of light, intensity of light or the direction light comes from