Connective Tissue Identifiaction

Areolar Tissue

Appearance: Loose network of fibers (collagen and elastic), scattered fibroblasts

Functions: Nourish and remove waste for epithelial Tissues; binds tissues together

Locations: Underlies epithelial tissue, surrounds nerves and blood vessels, the body’s “filler material”

Reticular Tissue

Appearance: Loose meshwork of reticular fibers and fibroblasts, infiltrated with leukocytes

Functions: Forms supportive stroma (framework) for lymphatic organs

Locations: Lymph nodes, spleen, bone marrow

Adipose Tissue

Appearance: Empty-looking cells with thin margins, nucleus pressed against the cell membrane, vascular

Functions: Energy storage, insulation, cushioning

Locations: Subcutaneous (under skin) breast, surrounds internal organs

Dense Regular Connective Tissue

Appearance: Densely packed, parallel collagen fibers, often wavy, compressed fibroblast nuclei

Functions: Withstands predictable stresses

Locations: Tendons attach muscle to bone and ligaments attach bone to bone

Dense Irregular Connective Tissue

Appearance: Densely packed collagen fibers running in random directions, few visible cells

Functions: Withstands unpredictable stresses; durable

Locations: Dermis of skin, capsules around organs

Elastic Connective Tissue

Appearance: Densely packed collagen fibers and elastic fibers

Functions: Expansion and recoil of tissue/organs

Locations: Walls of large arteries (aorta), vocal cords

Elastic Cartilage

Appearance: Abundance of elastic fibers in web-like mesh, chondrocytes in lacunae

Functions: Provides flexible, elastic support

Locations: External ear and epiglottis

Fibrocartilage

Appearance: Coarse bundles of parallel collagen fibers; rows of chondrocytes in lacunae between collagen fibers

Functions: Resists compression and absorbs shock

Locations: Pubic symphysis, meniscus of knee, intervertebral discs

Hyaline Cartilage

Appearance: Smooth/glassy matrix; chondrocytes in lacunae, often in small clusters

Functions: Eases joint movement, holds airway open, moves vocal cords, growth of long bones in children, precursor to fetal skeleton

Locations: Articular/joint cartilage on ends of long bones, costal (rib) cartilage, trachea, larynx, fetal skeleton

Osseous Tissue (Bone)

Appearance: Hard, calcified matrix arranged in concentric lamellae around a central canal; osteocytes in lacunae; osteons are the structural units of compact bone

Functions: Movement, mineral storage (calcium and phosphorus), framework of body, protection of viscera (internal organs)

Locations: Bones of the skeleton

Blood

Appearance: RBCs, WBCs, and platelets; fluid matrix (plasma)

Functions: Transports substances, contributes to immune defense

Locations: Inside blood vessels and heart