Skeleton Bones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue. Bones have a variety of shapes with a complex internal and external structure they are also lightweight, yet strong and hard. One of the types of tissue that makes up bone tissue is mineralized tissue and this gives it rigidity and a honeycomb-like three-dimensional internal structure. Other types of tissue found in bones include marrow, endosteum and
Adipose tissue lipids. There is a constant flux of FFA (Free Fatty Acids) entering and leaving adipose tissue. The net direction of this flux is controlled by insulin and leptin—if insulin is elevated, then there is a net inward flux of FFA, and only when insulin is low can FFA leave adipose tissue. Insulin secretion is stimulated by high blood sugar, which results from consuming carbohydrates. In humans, lipolysis (hydrolysis of triglycerides into free fatty acids) is controlled through the balanced control of lipolytic B-adrenergic receptors and a2A-adrenergic receptor-mediated antilipolysis. Fat cells have an important physiological role in maintaining triglyceride and free