• is abundant—it makes up part of every organ in the body. • is diverse in both structure and function.

Connective Tissues Derived from

1. Composed of varying cells and extracellular matrix. 2. Vascular. 3. Involve in the tissue repair.

Fixed Cells

Are very large cells specialized for storage of triglycerides; they predominate in a specialized form of connective tissue called adipose tissue .

The major cells of connective tissue proper, are elongated, irregularly shaped cells with oval nuclei that synthesize and secrete most components of the ECM.

Lie beneath membranes in loose connective tissue and along small blood vessels of organs. Contain chemicals, such as heparin, histamine, and proteolytic enzymes.

Cells that differentiate in connective tissue from precursor cells called monocytes circulating in the blood;  They function in ECM turnover, phagocytosis of dead cells and debris, and antigen presentation to lymphocytes.

• precursor cells • precursor of macrophages

Cells that differentiate from B lymphocytes and are specialized for the abundant secretion of specific antibodies (immunoglobulins).

Normally wander through all types of connective tissue proper, providing surveillance against bacterial invaders and stimulating tissue repair.

Three Major Components of Basement Membrane:

• Most abundant protein in body.  • 1/4 to 1/3 of total body protein, or 6% of total body weight.  • Synthesized within Fibroblasts.  • Strong, Flexible, Inelastic.  • Tendons, ligaments, skin, and bone.

• Consist of a protein called elastin.  • Has the ability to return to its original shape after being stretched or compressed, giving tissue an elastic quality.  • Synthesize by Fibroblast.

Elastic Fibers consist of what type of protein

• Short, thin collagen fibers.  • Branch to form a network that fill spaces between tissues and organs.  • Synthesize by Reticular Cell.

• A long, unbranched polysaccharide chain composed of repeating disaccharide units.  • It gives a very slippery quality to the fluids that contain it.  • Lubricant for joint cavities & major component of the vitreous humor of the eye.

• A monomer with large molecule that consists of 80 to 100 polysaccharides, called GLYCOSAMINOGLYCAN'S (Chondroitin & Sulfate).  • Aggregates trap large quantities of water, which allows them to return to their original shape when x compressed or deformed.

1. Enclosing and separating other tissues. 2. Connecting tissue to one another. 3. Supporting and moving parts of the body. 4. Storing compounds. 5. Cushioning and insulating. 6. Transporting. 7. Protecting

Classification of the Connective Tissue 

Location: It is a embryonic tissue from which connective tissues, as well as other tissues, arise

Structure:

• Comprises the bulk of the body.  • Adult fat or mature form of adipose tissue.  • White to dark yellow color.

Location: Subcutaneous Tissue of the Skin, Retroperitoneal, etc

• Fetal Fat or an Immature form of adipose tissue.  • Tan to reddish brown color

Location: Interscapulum and Inguinal Regions of Newborn.

Multiple lipid droplets in the cytoplasm

Single fat droplets in the cytoplasm

• Is one of the firmest structure in the body. • No nerves present.

The surface of nearly all cartilage is surrounded by a layer of

cartilage cells

within an extensive and relatively rigid matrix. the spaces in which they are located are called

• Main constituent of the adult skeleton.  • HARD CONNECTIVE TISSUE that consists of living cells and mineralized matrix.  • Specialized connective tissue composed of calcified extracellular material.  • Rich blood supply.

a. Provides solid support for the body, protects vital organs. b. Containing bone marrow (Blood cells are formed). c. Reservoir of calcium, phosphate, and other ions.

BONE DEVELOPMENT

This occurs in the development of FLAT BONES OF THE SKULL, MAXILLA and MANDIBLE.  • Derived from MESENCHYME CELLS.

• AKA ENDOCHONDRAL OSSIFICATION • Occurs in the formation of the bones of the BASE OF THE SKULL, VERTEBRAL COLUMN in the pelvis and in the EXTREMITIES.  • Derived from CARTILAGE MODEL.

A layer of dense connective tissue on the outer surface of bone, bound to bone matrix by bundles of type I collagen called perforating or Sharpey fibers.

• A thin layer of active and inactive osteoblasts, which lines all the internal surfaces within bone; osteoblasts here are also required for bone growth. • Covers all trabeculae around the marrow cavities.

All bones are lined on both INTERNAL _________, and EXTERNAL _________ surfaces by layers of connective tissue.

OSTEOBLASTS Secrete components of the initial matrix, called

IMPORTANT COMPONENTS OF OSTEOID

Act to maintain the matrix and detect mechanical stresses on bone.

Osteocytes Matrix

Maintain communication with adjacent cells via a network of long dendritic processes that extend through the matrix via narrow ________ radiating from each lacuna.

• Are very large cells.  • Formed by fusion of several blood monocytes, which locally erode bone matrix during osteogenesis.  • Macrophage • Bone remodeling.

• More solid, with almost no space between many thin layers, or lamellae.  • Cortical bone, which represents 80% of the total bone mass.

• Deeper areas with numerous interconnecting cavities, called cancellous (trabecular or _____) bone, constituting about 20% of total bone mass.  • Has spaces between trabeculae or plates, of bone and therefore resembles a sponge.

• Immature bone, is formed during OSTEOGENESIS or REPAIR and has a calcified matrix with randomly arranged collagen fibers.  • Except: Near the sutures of the Calvarias and in the insertions of some tendons.  • Irregular, interwoven array of collagen fibers, this type of bone has a lower mineral content.  • Often a higher proportion of osteocytes than mature lamellar bone.  • Less strength.

• Most bone in adults, COMPACT OR CANCELLOUS, is organized as ________.  • By the action of osteoclasts and osteoblasts, woven bone undergoes rapid turnover and is remodeled into ____________. • Characterized by MULTIPLE LAYERS OR LAMELLAE of calcified matrix.  • LAMELLAE are organize concentrically around small central canals containing blood vessels and nerves (OSTEON OR HAVERSIAN SYSTEM).

Refers to the complex of concentric lamellae surrounding a small central canal that contains blood vessels, nerves, loose connective tissue, and endosteum.