Cells and Fibers in Connective Tissues:
1. Fibroblasts- large, flat cells with branching processes. Present in several connective
tissues, and usually most numerous. Fibroblast migrate through connective tissues,
secreting fibers and components of ground substance of extracellular matrix
2. Adipocytes (fat cells)-connective tissues that store triglycerides (fat). Found deep in
skin and around organs such as heart and kidneys.
3. Mast cells- abundant alongside blood vessels that supply connective tissue. Produce
histamine-chemical that dilates small blood vessels and part of inflammatory response,
body’s reaction to injury or infection. Can also bind to, ingest, and kill bacteria.
4. White blood cells- not found in significant numbers of normal connective tissue. In
response to certain conditions they migrate from blood to connective tissues for
immune response. Eg. Neutrophil- gathers at sites of infection, and Eosinophils-migrate
to sites of parasitic invasion and allergic responses.
5.Macrophages- develop from monocytes (type of white blood cells). They have
irregular shape with short branched projections and are capable of engulfing bacteria
and cellular debris by phagocytosis
-Fixed Macrophages- reside is particular tissues (cannot move)
-Wandering Macrophages- have ability to move throughout tissue and gather at sites of
infection or inflammation to carry on phagocytosis. 6. Plasma cells- small cells that develop from a type of white blood cell called B
lymphocyte. They secrete antibodies, protein that attack or neutralize foreign
substances in body. Is an important part of immune response. They are found in many
places of body, but reside in connective tis