They often respond to Quorum sensing which is determined by the cell density. Bacteria cells secrete molecules that can be detected by other bacteria, Quorum sensing allows bacteria to sense the concentration of these signalling molecules to monitor the local density of cells. It used by bacteria to coordinate certain behaviors , such as the production of biofilms.
Protein would not be made. Like the above answer, the poor little cell would die.
Well, flowers give insects like bees and butterflies nectar. That's their food. In return, the insects spread the flower's pollen so that other plants like its type can be fertilized.
This is mutualism - a symbiotic relationship were two organisms benefit.
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