Instructor: Anthony Phillips
Course: BioSci 107
Date: 2025
Binding and Support:
Connective tissue (CT) binds, supports, and strengthens other tissues in the body.
Transport System:
Blood, a type of connective tissue, serves as a major transport system for the body.
Energy Reservoir:
Adipose tissue (fat) acts as a significant energy reserve.
Differences from Epithelia:
CT is not found on body surfaces (e.g., bones, cartilage, blood).
Can be highly vascularized, unlike cartilage which is avascular and tendons with minimal blood supply.
Similarities to Epithelia:
CT is supplied by nerves (except cartilage).
Connective tissue is made up of:
Extracellular Matrix (ECM): The non-cellular component.
Cells: Various specialized cells that function within the ECM.
Components:
Composed of a ground substance (GS) and protein fibers.
Ground Substance: Includes water, proteins, and polysaccharides.
Protein Fibers: Three major types:
Collagen Fibers: Strong and flexible support.
Reticular Fibers: Form neetworks for support (thin, branching structure).
Elastic Fibers: Allow tissues to stretch and return to shape.
Function of ECM: Dictates the properties of the various types of connective tissue (e.g., cartilage is firm and rubbery).
Key Ingredients:
Water
Proteins (e.g., gelatin)
Polysaccharides (e.g., glycosaminoglycans, or GAGS)
Types of GAGS:
Mucopolysaccharides that bind to core proteins forming proteoglycans.
Sulphated GAGs:
Examples include dermatan sulfate, heparin sulfate, keratan sulfate, and chondroitin sulfate.
Non-Sulphated GAGs:
Hyaluronic acid, responsible for water retention in the ground substance.
Hyaluronic Acid:
Lubricates joints, maintains eye shape, and aids in cell binding.
Chondroitin Sulphate:
Provides support in cartilage, bone, skin, blood vessels.
Keratan Sulphate:
Present in cartilage, corneas, and bone.
Fibroblasts:
Primary cells that secrete matrix components.
Adipocytes:
Store energy in the form of fat.
Macrophages:
Phagocytic cells that help in immune response.
Plasma Cells:
Derived from B lymphocytes; produce antibodies.
Mast Cells:
Release histamine to mediate inflammatory responses.
Leukocytes:
White blood cells that play key roles in immunity.
Types:
Embryonic Connective Tissue: Mesenchyme and mucous tissue.
Mature Connective Tissue:
Connective Tissue Proper: Loose and dense connective tissues.
Fluid Connective Tissue: Blood and lymph.
Supporting Connective Tissue: Cartilage and bone.
Loose Connective Tissue:
Includes areolar, adipose, and reticular tissues.
Dense Connective Tissue:
Divided into dense regular, dense irregular, and elastic tissues.
Cartilage Types:
Hyaline, elastic, and fibrocartilage.
Bone Types:
Compact and spongy bones.
Compact Bone:
Composed of tightly packed units called osteons.
Spongy Bone:
Porous structure found beneath compact bone, lacking osteons.
Osteogenic Cells:
Stem cells that develop into bone-forming cells.
Osteoblasts:
Responsible for bone formation.
Osteocytes:
Mature bone cells that maintain bone tissue.
Osteoclasts:
Cells involved in bone resorption.
Parts:
Lamellae: Concentric rings of minerals and collagen.
Lacunae: Spaces containing osteocytes.
Canaliculi: Tiny canals facilitating nutrient exchange.
Central canal: Houses blood vessels, lymphatic vessels, and nerves.
Depicts stages from injury, through inflammation, callus formation, to remodeling.
Composed of blood plasma and formed elements (red blood cells, white blood cells, and platelets).
Function of Blood Cells:
Red blood cells transport gases; white blood cells are involved in immune responses.
Connective tissue is essential for binding, supporting, and protecting other tissues and organs in the body. It plays a critical role in transportation, energy storage, and storage of key Components.