Connective tissue provides support and nourishment to other tissues and organs. It protects the organs and helps repair any damaged tissues. The connective tissue cell types include fibroblasts, adipocytes, and smooth muscle cells, among others. Fibroblasts are the most abundant and the least specialized cells among the connective tissue family. They are elongated and spindle-shaped cells that secrete extracellular matrix molecules and help in wound healing. Fibroblasts can also transform into bone cells, chondrocytes, or adipocytes, other connective tissue cell family members. Adipocytes are roughly circular or polyhedral in shape and contain a large lipid droplet surrounded by a thin layer of cytoplasm. Adipocytes store energy in the form of lipids and help maintain body temperature. They also play a major role in glucose and energy homeostasis. Smooth muscle cells are elongated cells that contain thin filaments composed of actin and thick filaments composed of myosin. Smooth muscle contraction facilitates essential functions, for example, movement of food along the gastrointestinal tract or regulation of blood flow.