Connective Tissue

Connective Tissue

Connective Tissue

Most abundant and widely distributed of primary tissues

Clasess of connective tissue

• Connective tissue proper

• Cartilage

• Bone

• Blood

Functions of connective tissue

• Binding and support

• Protecting

• Insulating

• Storing Reserve fuel

• Transporting substances (blood)

Characteristics of connective tissue

• Have mesenchyme (an embryonic tissue)

• Have varying degrees of vascularity (blood vessels)

• Have extracellular matrix

Elements of connective tissue

• Ground substances

• Fibers

• Cells

Ground substances

Unstructured material that fills the space between cells

Connective tissue fibers

• Collagen

• Elastic fibers

• Reticular

Blast cells

• Immature form; mitotically active; secrete ground substances and fibers

• Fibroblasts in connective tissue proper

• Chondroblasts in cartilage

• Osteoblasts in bone

• Hematopoietic stem cells in bone marrow

Cyte Cells

• Mature form; maintain matrix

• Chondrocytes in cartilage

• Osteocytes in bone

Mast Cells

Initiate local inflammatory response against foreign microorganisms they detect

Macrophages

Phagocytic cells that “eat” dead cells, microorganisms; function in immune system

Areolar Connective Tissue

• Function: Wraps and cushions organs

• Location: Widely distributed under epithelia of the body

Epithelia

skin

Types of Connective Tissue

Two subclasses

• Loose connective tissues

  • Areolar

  • Adipose

  • Reticular

• Dense connective tissues

  • Dense regular

  • Dense irregular

  • Elastic

Adipose Tissue

Pretty much the fat tissue. The cell is adipocyte which stores nutrients.

Adipose connective tissue

• Function: Reserve food fuel, insulates, and supports/protects organs

• Location: Around kidney and eyeballs and found in breasts.

Dense regular connective tissue

• Closely packed bundles of collagen fibers running parallel to direction of pull

  • White structures with great resistance to pulling

  • Fibers slightly wavy so stretch a little

• Fibroblasts manufacture fibers and ground substance

• Few cells

• Poorly vascularized

Dense regular connective tissue

• Function: Attaches muscle to muscle, muscle to bone, or bone to bone. Can also withstand great stress

• Location: Tendons and ligaments

Elastic connective tissue

• Some ligaments very elastic

  • Those connecting adjacent vertebrae

• Many of larger arteries have in walls

Elastic connective tissue

• Function: maintains flow of blood

• Location: Walls of large arteries near the heart

Cartilage

• Chondroblasts and chondrocytes

• Tough yet flexible

• Lacks nerve fibers

• Up to 80% water - can rebound after compression

• Avascular

  • Receives nutrients from membrane surrounding it

    • Perichondrium

Three types of cartilage

• Hyaline cartilage

• Elastic cartilage

• Fibrocartilage

Hyaline cartilage

• Function: Supports and reinforces

• Location: The ribs and the nose

Elastic cartilage

• Function: Maintains shape and allows for flexibility

• Location: Supports the external ear (pinna); epiglottis

Fibrocartilage

• Function: Allows it to absorb compressive shock

• Location: Discs of knee joint

Osseous tissue

• Function: Same as bone

• Location: Bones