Activity 9: For You To Do
1. a) Without thorough cleaning, contaminants may be inadvertently introduced
into the experiment.
4. a) How do phosphates affect algal growth?
How do phosphates and nitrates affect algal growth?
b) Jar C is the control.
7. a) Algal growth will be greatest in Jar B with fertilizer since both phosphates and nitrates that are needed by the algae are present in huge amounts. Algal growth will be least in Jar C since phosphates and nitrogen are not present in huge amounts.
11. b) Student answers may vary. The findings support what has been predicted since both phosphates and nitrogen, which are necessary for algal growth and development, are present in the fertilizer.
Using Blackline Master Ecology 9.3: Effect of Detergent and Lawn Fertilizer on Algal Growth discuss with the students what characteristics they should look for
in their jars to describe the developments that are occurring. Emphasize the importance of keeping good records. To prevent loss of experimental results,
require the groups not to have just one student keep records but that every single member should do so. |