HPP LEC MIDTERM

• Components of Skeletal System

  Bones Cartilages Tendons Ligaments
• Skeletal System Functions

  1. Support 2. Protect 3. Movement 4. Storage 5. Blood cell production
• Connective Tissues

  Bones

  Ligaments

  Tendons

  Cartilages
• tough, ropelike protein.

  Collagen
• large molecules consisting of many polysaccharides attaching to and encircling core proteins.

  Proteoglycans
• large aggregates and attract water.

  Proteoglycans
• The extracellular matrix of tendons and ligaments contains large amounts of collagen fibers, making these structures very 


  very tough, like ropes or cables.
• The extracellular matrix of cartilage contains

  collagen and proteoglycans.
• The extracellular matrix of cartilage contains

  collagen and proteoglycans.
• is relatively rigid, but it springs back to its original shape after being bent or slightly compressed.

  It is an excellent shock absorber

  Cartilage
• The extracellular matrix of bone contains

  collagen and minerals, including calcium and phosphate.
• The extracellular matrix of bone contains

  collagen and minerals, including calcium and phosphate.
• The mineral component gives

  gives bone compression (weight-bearing) strength.
• are longer than they are wide; examples are upper and lower limb bones.

  Long bones
• approximately as wide as they are long; examples are the bones of the wrist and ankle.

  Short bone
• have a relatively thin, flattened shape; examples are bones of the skull and sternum.

  Flat bones
• include the vertebrae and facial bones, which have shapes that do not fit readily into the other three categories

  Irregular bones
• Long Bone Structure is composed of 1.Diaphysis

  2.Epiphysis

  3.Articular Cartilage

  4.Epiphyseal Plate

  5.Medullar Cavity

  6.Periosteum

  7.Endosteum
• Articular cartilage - Covers the epiphyses to reduce friction between bones during movement.
• Epiphysis - Head of the bone.
• Diaphysis - Shaft or body of the bone.
• Compact (Cortical) Bone - Hard outer layer of bone tissue.
• Compact bone - Dense layer surrounding medullary cavity.
• Periosteum - Outer covering of compact bone.
• Metaphysis - Junction of diaphysis with epiphysis.
• the location of blood forming cells

  Red Marrow
• is mostly fat.

  Yellow marrow
• most bones have blood making red bone marrow.

  Newborns
• red marrow in the diaphysis is replaced by yellow bone marrow.

  Adults
• Compact Bone Tissue is composed of

  Osteons-structural unit of compact bones

  Lacunae-spaces between lamella

  Lamella- rings of bone matrix

  Central canal- center of osteons and contain blood vessels

  Canaliculus-tiny canals , tranports nutrients by the process of diffusion
• Compact Bone Tissue is composed of

  Osteons-structural unit of compact bones

  Lacunae-spaces between lamella

  Lamella- rings of bone matrix

  Central canal- center of osteons and contain blood vessels

  Canaliculus-tiny canals , tranports nutrients by the process of diffusion
• • It is located at the epiphyses of long bones and center of other bones. • It has trabeculae, which are interconnecting rods, and spaces that contain marrow. • It has no osteons.

  Spongy bone
• responsible for the formation of bone and the repair and remodeling of bone.

  Osteoblasts
• cells that maintain bone matrix and form from osteoblast after bone matrix has surrounded it.

  Osteocytes
• contribute to bone repair and remodeling by removing existing bone, called bone reabsorption.

  Osteoclasts
• is the formation of bone by osteoblasts.

  Ossification
• Bone formation that occurs within connective tissue membranes is called

  Intramembranous ossification
• Bone formation that occurs inside hyaline cartilage is called

  endochondral ossification
• occurs when osteoblasts begin to produce bone within connective tissue. This occurs primarily in the bones of the skull. Osteoblasts line up on the surface of connective tissue fibers and begin depositing bone matrix to form trabeculae.

  Intramembranous ossification
• occurs when osteoblasts begin to produce bone within connective tissue. This occurs primarily in the bones of the skull. Osteoblasts line up on the surface of connective tissue fibers and begin depositing bone matrix to form trabeculae.

  Intramembranous ossification