Answer:
Capture of light energy
Explanation:
I just completed this test on E2020.
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.
first left (up) trachea
first left (down) diaphragm
right (up) bronchiole
right (down) alveolus
The answer to your question is Letter C <-- ANSWER
Steroid is a molecule made up of four carbon rings with other atoms bonded to those rings.
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