four basic types of tissue

Adipocytes

also called fat cells, are connective tissue cells that store triglycerides (fats). They are found below the skin and around organs such as the heart and kidneys.

Mast cells

are abundant alongside the blood vessels that supply connective tissue. They produce histamine, a chemical that dilates small blood vessels as part of the inflammatory response, the body's reaction to injury or infection. Can also kill bacteria.

Fibroblasts

are large, flat cells with branching processes. They are present in several connective tissues, and usually are the most numerous. Migrate through the connective tissue, secreting the fibers and ground substance of the extracellular matrix.

Plasma cells

are small cells that develop from a type of white blood cell called a B lymphocyte. secrete antibodies, proteins that attack or neutralize foreign substances in the body. Thus, are an important part of the body's immune response.

Collagen fibers

are very strong and resist pulling forces, but they are not stiff, which promotes tissue flexibility. These fibers often occur in bundles lying parallel to one another.

Reticular fibers consisting of

collagen and a coating of glycoprotein

Three types of fibers are embedded in the extracellular matrix between the cells:

collagen fibers, elastic fibers, & reticular fibers.

Chemically, collagen fibers consist of the protein

collagen.

Epithelial tissue

covers body surfaces; lines body cavities, hollow organs, and ducts (tubes); and forms glands.

Nervous tissue

detects changes inside and outside the body and initiates and transmits nerve impulses (action potentials) that coordinate body activities to help maintain homeostasis.

Macrophages

develop from monocytes, a type of white blood cell. Have an irregular shape with short branching projections and are capable of engulfing bacteria and cellular debris by phagocytosis.

Elastic fibers consists of molecules of a protein called

elastin surrounded by a glycoprotein named fibrillin, which is essential to the stability of an elastic fiber.

ground + protein fibers=

extracellular matrix

Muscular tissue

generates the physical force needed to make body structures move.

Fibers

in the extracellular matrix strengthen and support connective tissues.

Connective tissue

protects and supports the body and its organs, binds organs together, stores energy reserves as fat, and provides immunity.

Reticular fibers

provide support in the walls of blood vessels and form branching networks around fat cells, nerve fibers, and skeletal and smooth muscle cells.

Ground substance

the component of a connective tissue between the cells and fibers, supports cells, binds them together, and provides a medium through which substances are exchanged between the blood and cells. plays an active role in how tissues develop, migrate, proliferate, and change shape, and in how they carry out their metabolic functions.

Elastic fibers

which are smaller in diameter than collagen fibers, branch and join together to form a network within a tissue.