Connective Tissue• The dense layer of the basal lamina of all epithelial

tissue is created by connective tissue. • Connective tissue connects the epithelium to the

rest of the body.

Three Basic Components

1. Specialized cells– Fibroblasts– Adipocytes

2. Extracellular protein fibers– Collagen fibers– Reticular fibers– Elastic fibers

3. A fluid known as ground substance

Functions of Connective Tissue

• Establishing a structural framework for the body.• Transporting fluids and dissolved minerals.• Protecting delicate organs.• Supporting, surrounding, interconnecting other types

of tissue.• Storing energy reserves• Defending the body from invading microorganisms.

Classification of Connective TissuesClassified based on their physical properties. Three categories:• Connective Tissue

Proper– Ex. Adipose tissue

• Fluid Connective Tissue– Ex. Blood and Lymph

• Supportive Connective Tissue– Ex. Cartilage and bone

Connective Tissues

Connective Tissue Proper Fluid Connective Tissues Supporting Connective Tissues

LOOSE DENSE

Fibers create loose, open framework. “Packing materials”• Adipose• Areolar• Reticular

Fibers densely packed• Dense

regular• Dense

Irregular• Elastic

BLOOD LYMPH

Contained in cardiovascular system

Contained in lymphatic system

CARTILAGE BONE

Solid, rubbery matrix• Hyaline• Elastic• Fibrocartilage

Solid, crystalline matrix

Mesenchyme Tissue

• Function: Give rise to all other connective tissues of an embryo and all various cell types of adult connective tissue.

• Found in abundance during early development of most animals.

Loose Connective Tissue• Adipose Tissue

– Location: Deep to the skin, especially at sides, buttocks, padding around eyes and kidneys

– Function: Provides padding, insulates, stores energy

• Areolar Tissue– Location: Under skin, in or

around mucous membranes, around blood vessels and nerves

– Functions: provides padding, binds the outer layer to the muscles beneath.

Dense Regular Connective Tissue

Ex. Tendons and Ligaments• Locations: Between

skeletal muscles and skeleton; between bones or internal organs

• Functions: Provides firm attachment, conducts pull of muscles, reduces friction

Elastic Tissue

• Location: Between vertebrae of the spinal column; in blood vessel walls

• Functions: Stabilizes positions of vertebrae; cushions shocks

Cartilage• The matrix of cartilage is a firm gel that contains

polysaccharide derivatives• Chondrocytes- Cartilage cells, the only cells in the

cartilage matrix• Lacunae- Small chambers that cartilage cells occupy

Hyaline Cartilage

• Locations: Between tips of ribs and bones of sternum; supporting larynx, trachea, and bronchi

• Functions: Provides stiff but flexible support, reduces friction between bony surfaces

Elastic Cartilage

• Locations: In the ear and in the trachea

• Functions: Provides support, but tolerates distortion without damage and returns to original shape

Fibrous Cartilage

• Locations: Pads within knee joint; between pubic bones of pelvis; intervertebral discs

• Functions: Resists compression; prevents bone-to-bone contact; limits relative movement