HistologyPart II: Connective Tissue

MMHS Anatomy

Location and DescriptionLocation:Found throughout the body but never exposed to

the external environment.Description:Made up of specialized cells.Contains extracellular protein fibers called

“matrix”.“Ground Substance” fluid found throughout.May or May not be highly vascularized.

Bone, Blood, Loose Connective, Adipose = VascularCartilage, Dense Connective = Poorly vascularized

Functions of Connective Tissue

1. Provides a structural framework of the body.

2. Transports Fluids3. Binds together other body tissues.4. Protection of vital internal

organs.5. Stores long-term energy.

Classification of Connective Tissue

Loose ConnectiveContains a disorganized “packing material” that fills spaces between organs and cushions and supports epithelia.

Adipose tissue: looks like droplets of lipids: functions to pad and insulate the body.

Nuclei are squished to the side.

Dense Connective

Collagen fibers dominated this tissue.

Fibers are tightly packed and run parallel to each other.

Fibers often have “wavy” appearance.

Examples: tendons, ligaments, and elastic tissue.

BloodRed blood cells (erythrocytes) = the most

numerous and biconcave-shaped cells. Transport gases.

White blood cells (leukocytes)= fewer in number; large, irregularly-shaped, fight diseases.

Plasma = made up of a watery fluid.Platelets (thrombocytes)= fragments of

cells that clot blood.

Hyaline Cartilage

Most common type of cartilageCollagen fibers are so closely

packed and so appear to be absent..Locations: Connections between ribs, coverings of elbow and knee.

Compact Bone

Made up of collagen fibers and calcium salts.

Lacunae (compartments within bone) contain osteocytes.

Bone tissue is highly vascularized = diffusion of gases occurs between osteocytes through canaliculi.

Spongy “Cancellous” Bone

Made up of bone columns called trabeculae.

Lacunae contain osteocytes.Spongy Bone tissue contains red marrow. Found in the ends of long bones called

epiphyses.Cushions impact during falls and

distributes force to the compact bone. Contains many air spaces in the tissue.