Question

What might happen to the food web below if the number of phytoplankton drastically decreased?
1. small fish and wading birds would be affected.
2. Only the small fish would be affected.
3. The small fish, bivalves, and invertebrates would be affected.
4.The entire food web would be affected.

Answer 1

The entire food web would be affected.  if the creature that eats phytoplankton has nothing to eat, it will die, then the creature that relies on that creature would die and so on

Answer 2

The correct answer is option 4. The entire food web would be affected.

The phytoplanktons are the major primary producers of the aquatic ecosystem. Many small fishes eat the phytoplanktons directly. In case, the phytoplanktons are missing, productivity of the ocean decreases, the small fishes cannot get their food and their number decrease. The other aquatic or non aquatic organism, which feed on small fishes would also be affected. Hence, the decrease in phytoplanktons would affect the whole food web.