Can you help me complete this Pre-Lab Biology assignment??

Bio 112 Pre-Lab 8
1. If you took Bio 111 here, you performed experiments with Daphnia, the small
aquatic animal which was our test subject for our drug experiments. Studtnet
often ask about the fate of the ?leftover? Daphnia at the end of the week. The
answer is that they becime part of the ?Daphnia farm.? The farm is basically a
large glass jar, inside the jar we put pH-balanced pond water and Elodea, an
aquatic plant. Green algae, small microscopic plants, grow on the sides of the
jar. An occasional worm or snail may be seen in th the farm, as those animals
often ?hitchhike? on the Elodea we put into the jar. The jar is sealed by a piece
of plastic or glass and stored next to a window. All organisms live successively
in the jar.
What is the ultimate source of energy for this ecosystem?
Which organism in the ?farm? an directly tap into that energy source?
Which of the organisms in the ?farm? are animals?
How would the animals in the ?farm? obtain the chemical energy they need for
survival in the jar?
2. Circle the appropriate tropic level for each organism in the ?Daphnia farm?
listed below
Organism
Elodea
Consumer, Decomposer or producer
Daphnia
Consumer, Decomposer or producer
Snail
Consumer, Decomposer or producer

3. Suppose someone added phosphates to the ?Daphnia farm?
What would we expect to happen to the population size of the algae?
Exaplin.
What would we expect to be the subsequent effect on the population size of
the Daphnia?
Explain
4. Students topk samples from the creek at an area just downtown from the
soccer fields on campus. They got a nitrate concentration reading of 4 ppm

(parts per million). In the next week , they repeated their water sampling at
the same location and found the nitrate concentration to be 8 ppm.
What might have caused the increase in nitrate concentration over a week?s
time?
What effect would an increase in nitrate concentration in the water have on
the growth of aquatic plants in the creek?
Explain
What effect would an increase in nitrate concentration in the water have on
the concentration of dissolved oxygen in the creek?
Explain.