Bones Quiz

• Bones: organs of skeletal system and are composed of many tissues

• Tissues:  bone tissue, cartilage, dense connective tissue, blood, and nervous tissue

• bones are alive and multifunctional

  •  supports and protects soft tissues

  •  provides points of attachment for muscles

  •  houses blood producing cells

  •  stores in organic salts

•  very in size and shape

  •  long bones

    •  long and narrow

    •  have expanded ends

    • PARTS:

      •  Epiphysis:  expanded end

      •  Diphysis:  bone shaft

      •  Metaphysis:  between diaphysis and Ephysis, widening part

      •  articular cartilage: covers Ephysis 

      • Periosteum: encloses bone; dense connective tissue

      •  Compact (coritcal)  bone: wall of diaphysis

        •  consists of cylindrical units called osteons

          •  osteons are osteocytes in lacunae

        •  strong and solid

        •  Weight-bearing

        •  resists compression

      •  Spongy (cancellous) bone: makes up epiphysis

        •  consists of branching plates called trabeculae

        •  somewhat flexible

        •  has spaces between trabeculae that reduce the bones weight

      •  Trabeculae:  branching bony plates, make up spongy bone

      •  medullary cavity: Hollow chamber and diaphysis: contains marrow

      •  Endosteum:  lines space, cavity

      •  bone marrow: red or yellow marrow, lines medullary cavity, spongy bone spaces

      • Lamallae:  layers of Matrix around central canal

      •  osteons cemented together by bone matrix

      •  Perforating Canal join adjacent Central canals

      •  blood vessels provide nutrients to Bone tissue

      •  osteocytes can pass nutrients through canaliculi

  •  short bones

    •  Cube-like, length = width

    •  includes sesamoid (round) bones which are embedded in tendons

  •  flat bones

    • plate-like, with broad surfaces

  •  irregular bones

    •  variety of shapes

    •  most are connected to several other bones

•  similar in structure, development, and function

•  major functions of bones 

  • Provide shape to body

  •  support body structures

    • Bones provide shape for head, face, thorax, limbs

    •  bones support body weight (bones of lower limbs, pelvis, vertebral column)

    • Skull bones protect brain, ears, and eyes

    •  bones of rib cage, shoulder, girdle, protect heart, lungs

    •  bones of pelvic girdle protect internal reproductive organs, lower abdominal organs 

    • Bones + muscles provide movement

  •  protect body structures

  •  Aid body movements

  •  contain tissue that produces blood cells

  •  stores in organic salts

 blood cell function

• Hematopoiesis:  blood cell formation

•  blood cell production occurs in red bone marrow

•  red blood cells, white blood cells, and platelets are produced in red bone marrow

Inorganic Salt storage 

• About 70% of bone matrix consists of inorganic mineral salts

•  most abundant salt is Crystals of hydroxypatite (calcium phosphate)

•  other salts:

  •  magnesium ions

  •  sodium ions

  •  potassium ions

  •  Carbonate ions

•  osteoporosis: condition that results from loss of bone mineralization

•  since calcium is vital in nerve impulse conduction and muscle contraction, blood calcium levels are regulated by parathyroid hormone and calcitonin

•  206 bones in adults skeleton

  •  some people have more, some people have less

  •  extra bones are called Sutural (wormian) bones in sutures between major skull bones

  •  small sesamoid bones are in tendons; reduces friction

• Axial (80 bones)

  •  Skull

  •  Middle ear

  •  Hyoid bone

  • Vertebral column

  •  thoracic cage

• Appendicular (126 bones)

  •  pectoral girdle

  •  upper limbs

  •  pelvic girdle

  •  lower limbs