tissue, also known as fat tissue, serves many purposes within the body. Its two most important functions are heat insulation
and energy transformation.
tissue acts as a insulator, trapping heat around the vital organs in the body, as well as providing cushioning to the body,
surrounding organ structures and protecting them from damage. Fat also provides the body with shape, such as in the breasts
and hips in women.
adipose tissue acts as a source of energy when the body does not receive as much glucose as it needs. Excess energy from carbohydrates
are synthesized by the liver, and stored in the form of lipids in adipose cells. Fat is useful as a backup for energy use
because it can be stored easily without using much water, and provides more energy per gram than carbohydrates.
cells, called adipocytes, can be subdivided into two classes, white adipose tissue, and brown adipose tissue. White adipose
tissue is much more common than brown fat, and is used mainly as energy storage in times of low carbohydrate consumption.
Brown adipose tissue, however, is metabolized mainly for the release of heat and is commonly found in animals that hibernate,
or live in colder conditions.
of white and brown adipose tissue is also different. White fat is composed mainly of globular cells containing large lipid
vacuoles, with the few mitochondria and the nucleus of the cell being found near the edge of the cell.
cells are smaller than white fat cells, and contain smaller lipid vacuoles as well as many more mitochondria. The presence
of numerous mitochondria causes the brown coloring of these adipocytes, which also receive more capillary blood flow than
their white counterparts.
contained in adipocytes are composed mainly of triglycerides, although they do contain small amounts of free fatty acids,
diglycerides, monoglycerides, cholesterol and phospholipids.
occurs when there is a large amount of adipocytes in the body which exceed the needed fat storage of the body. This is unhealthy
for organ systems, and is caused by a number of factors, such as inactivity, overeating, and genetic, environmental, physiological,
and psychological factors.