Heterocyst-forming cyanobacteria differentiate highly specialized cells to provide fixed nitrogen to the vegetative cells in a filament. In the presence of a source of combined nitrogen such as nitrate or ammonium, Anabaena PCC 7120 grows as long filaments containing hundreds of photosynthetic vegetative cells.
Answer:
One significant difference that I noticed was the color of the water. In the control aquarium, the color of the water at 30 days was the same as it was on the 1st day. In the experimental aquarium, the water had a green tint on the 30th day, but on the first day it was clear.
The answer is D) the organ system.
I'd say protein synthesizer.
I'm not sure what you mean by "compartments", but the cardiovascular system consists of the heart, blood vessels, and approximately 5 liters of blood.