Explanation: Tissues are groups of similar cells that have a common function. An organ is a structure that is composed of at least two or more tissue types and performs a specific set of functions for the body. Many organs working together to accomplish a common purpose is called an organ system.
An important example of negative feedback is the control of blood sugar. After a meal, the small intestine absorbs glucose from digested food. Blood glucose levels rise. Increased blood glucose levels stimulate beta cells in the pancreas to produce insulin.