The key evolutionary development of animals seen for the first time in sponges is that of Multicellularity. A Multicellular organism has a longer lifespan than an unicellular organism and since it has multiple cells, it can perform more functions. Sponges do not have distinct circulatory, respiratory, digestive, and excretory systems – instead the water flow system supports all these functions.
The period you’ve described would be the G2 phase which is considered a “checkpoint” that determines whether or not a cell can enter the mitosis phase
Answer:
Answer is bile
Cholecystokinin is secreted by cells of the upper small intestine. Its secretion is stimulated by the introduction of hydrochloric acid, amino acids, or fatty acids into the stomach or duodenum. Cholecystokinin stimulates the gallbladder to contract and release stored bile into the intestine.
