Module 4.3: Connective Tissue

Connective Tissue Functions

Functions include connecting and binding, support, protection, and transport.

Resident cells vs. migrant cells

Resident cells inhabit a tissue permanently while migrant cells move to areas where their function is needed.

Fibroblasts

The most common resident cell in connective tissue that produces ground substance and protein fibers.

Adipocytes

Cells that dominate in cytoplasm with lipid inclusions, primarily involved in fat storage.

Mast Cells

Large resident cells of the immune system that release inflammatory mediators upon stimulation.

Phagocytes

Cells that ingest foreign substances and dead cells through phagocytosis, including macrophages and neutrophils.

Loose Connective Tissue

Also called areolar connective tissue, it's primarily made of ground substance and supports other tissues.

Dense Irregular Connective Tissue

Characterized by collagen fibers arranged in multiple planes, providing strength in many directions.

Dense Regular Collagenous Tissue

Characterized by collagen fibers arranged in one plane, providing strength in that plane; found in tendons and ligaments.

Reticular Tissue

Contains reticular fibers that form mesh-like structures, providing support to blood and lymphatic vessels.

Adipose Tissue

Connective tissue made up primarily of adipocytes that provide insulation, shock absorption, and energy reserve.

Cartilage

Type of connective tissue with solid gel-like ECM that is tough yet flexible, found in joints, ears, and respiratory pathways.

Chondroblasts

Cells that actively divide and produce most of the ECM of cartilage.

Chondrocytes

Mature cartilage cells that inhabit lacunae in the ECM.

Hyaline Cartilage

Most abundant type of cartilage, with a glassy appearance used in joints and areas requiring support.

Fibrocartilage

Type of cartilage dominated by collagen fibers, providing tensile strength and flexibility, found in intervertebral discs.

Elastic Cartilage

Cartilage filled with elastic fibers, found in areas like the external ear.

Bone

Specialized connective tissue composed of organic and inorganic components; supports body structure.

Osteoblasts

Bone cells responsible for synthesizing the organic components of bone.

Osteocytes

Mature bone cells that maintain the bone matrix and reside in lacunae.

Osteoclasts

Multinucleated cells that break down bone tissue through bone resorption.

Blood

A fluid connective tissue with an ECM called plasma, containing cells that transport oxygen and aid in immunity.

Erythrocytes

Red blood cells that bind and transport oxygen throughout the body.

Leukocytes

White blood cells that function in the immune response.

Ground Substance

The non-cellular material in connective tissue that fills the space between cells and fibers.

Extracellular Matrix (ECM)

A complex network of proteins and carbohydrates that provides structural and biochemical support to surrounding cells.

Calcium phosphate crystals

Inorganic component of bone that provides strength and rigidity.

Perichondrium

The dense irregular connective tissue that envelops cartilage.

Shock Absorption

The function of connective tissues like fat and cartilage to absorb impact and prevent damage to organs.

Connective Tissue Proper

Includes loose and dense connective tissues, characterized by various types of cells and ECM components.

Specialized Connective Tissues

Includes cartilage, bone, and blood, each with unique structural and functional properties.