Fat cells and adipose tissue

Fat cells are normally present in loose connective tissue either singly or in small groups. Fat cells are created from stem cells in fatty tissue that develop into mature, long-lived fat cells that signal immature fat cells to divide and reproduce as needed throughout life to store excess calories as fat and to disappear when no longer needed. When large numbers of these cells are organized, the resulting lobules constitute adipose tissue.

Adipose tissue is sometimes referred to simply as fat. Adipose tissue may be partitioned by connective tissue septa into lobules. While in the subsequent developmental phases the lobules continuously increase in size.

The special capability of fat cells is the storage of a fuel reserve, which may vary in extent from an approximate 40-day reserve in the average person to one sufficient for a year or more in some obese individuals.

Brown adipose tissue

At first, fat cells were thought to be placid repositories of excess fuel which, when organized into subcutaneous layers, served as insulting material to prevent loss of body heat.

When the individual is on reducing diet, adipose tissue undergoes a process called lipolysis. Lipolysis is the separation of fatty acids from the stored form of fat, and release of the fatty acids into the blood so that they can be used by tissues and organs as a source of energy.

Another recognized function of adipose tissue was it ability to cushion, support abdominal organs and shapes the body.
Fat cells and adipose tissue