Question

50 POINTS PLS HELP ILL GIVE BRAINLEST

Cyanobacteria are photosynthetic single-celled organisms that thrive on the sunlight and nutrients. Cyanobacteria blooms (blue-green algae) are a frequent occurrence in the Great Lakes, particularly in Lake Erie, Green Bay, and Saginaw Bay in August and early September. Which statement(s) describes the main cause(s) of the cyanobacteria blooms in the Great Lakes?

I. Increase in human population and activities such as industrialization and agriculture.
II. The nutrient levels of the Great Lakes are lower due to increased pollution.
III. Low oxygen levels in the Lakes attract cyanobacteria.

A. I only
B. II only
C. I and II
D. II and III

Answer 1

The statement that describes the main cause of the cyanobacteria blooms in the Great Lakes would be an increase in human population and activities such as industrialization and agriculture. Hence, the correct option would be A.

The bloom of algae (cyanobacteria inclusive) in water bodies is caused by enrichment of the water by nutrients such as phosphorus and nitrogen. The phenomenon is known as eutrophication.

Enrichment of water bodies often result from human activities such as pollution of the aquatic environment from industrial wastes and agricultural wash down of fertilizers.

In other words, lower nutrient or oxygen levels do not cause eutrophication. Low oxygen level could, however, be one of the effects of eutrophication.

More on eutrophication can be found here: https://brainly.com/question/17257452

Answer 2

Answer:

A. I only

Explanation: