Answer:
541 million years ago with the Cambrian explosion, an extraordinary diversification of marine animals, and ended about 252 million years ago with the end-Permian extinction, the greatest extinction event in Earth history.
source- Britannica
Explanation:
The esophagus has a simple but significant functions to animals who has it. These functions can be a) to swallow food and serve as a passageway to the stomach and b) may serve to release the eaten food that might have some harmful compositions or chemicals -the vomit response.
It provides the reader with your topic and give them a central idea of your writing.
Autoinducer molecules are signalling molecules that need bacteria. In order for the autoinducer molecules to signal, the bacteria must find a way to initiate the signal and a way to respond to the signal it had created. Autoinducer molecules increase in production as the density of the bacteria cell increases.