The Skeletal System

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The Skeletal System
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Skeletal System

• Bony tissues that form the bodys framework
  comprise the Skeletal System.
• In domesticated animals, the skeletal system is
  internal, called an endoskeleton, and are
  basically alike in most species.

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Skeletal System

• The number of bones in a horses neck are the
  same as those in a rabbits, but the size and
  length vary.

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Skeletal System

• The outer layers of bones are composed of hard
  mineral deposits. About 26 of total bone mass
  is composed of mineral matter.
• The remainder of the composition of bones
  includes 20 protein, 4 fat, and 50 water.

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Skeletal System

• About 85 of the mineral matter is calcium
  phosphate.
• The remaining 15 is calcium carbonate.

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Skeletal System

• The inner core of bones is soft tissue called
  bone marrow.
• Some of the bone marrow consists of yellow fat,
  called yellow marrow.
• The other portion is made of red tissue called
  red marrow, that is responsible for red blood
  cell formation.

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Skeletal System

• As an animal grows, bones increase in size and
  length in the region of cartilage between the end
  and shaft of bones.
• As the animal matures, this cartilage ossifies
  (becomes bony material).

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Skeletal System

• In mature animals, bone is continually being
  reabsorbed and replaced, but no new bone growth
  occurs.
• Osteoporosis occurs when the bone that is
  reabsorbed is not replaced.

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Skeletal System

• As long bones grow in length, they also increase
  in diameter.
• This is caused by the production of new bony
  tissue in the periosteum that surrounds the
  outside of the bone.

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Skeletal System

• Bone growth is affected by hormones, vitamins,
  and other nutrients.
• Therefore, bones can become fragile or distorted
  due to nutritional deficiencies.
• Breaks in bones repair when the ends fill with a
  fibrin clot, that becomes bony tissue.

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Skeletal System

• The skeletal system provides body support and
  leverage for muscle movement, which is made
  possible by several types of joints.

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Skeletal System

• Ball-and-socket joints can move in all directions
  (shoulder).
• Hinge joints move in only two directions (knee).
• Pivot joints allow for movement in several
  directions (neck)

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Skeletal System

• Gliding joints allow for flexibility to move
  forward, backward, or sideways (vertebrae)

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Skeletal System

• Joints are held together by ligaments and are
  enclosed by a capsule which contains synovial
  fluid to lubricate the joint and allow
  friction-free movement.

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Skeletal System

• The skeletal system of animals of the phylum
  Chordata can be divided into three parts
• the axial (spine, ribs, sternum, skull)
• the pectoral limb (foreleg)
• the pelvic limb (pelvic girdle and hindlegs)

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Skeletal System
Axial -
Pelvic -
Pectoral -
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Skeletal System

• The vertebral column (spine) is divided into five
  regions
• Cervical (7 vertebrae)
• Thoracic (13 vertebrae)
• Lumbar (6 vertebrae)
• Sacral (5 vertebrae)
• Coccygeal (18-20 vertebrae)

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Skeletal System - Axial
Skull
Lumbar Vertebrae
Thoracic Vertebrae
Sacral Vertebrae
Coccygeal Vertebrae
Ribs
Cervical Vertebrae
Xyphoid
Sternum
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Skeletal System - Pectoral
Scapula
Humerus
Ulna
Radius
Metacarpal Bones
Carpus
Phalanges
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Skeletal System - Pelvic
Ilium
Pelvis
Ischium
Femur
Patella
Tibia and Fibula
Tarsus
Metatarus
Phalanges
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Skeletal System
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Maxillar
Mandible
Clavicle
Scapula
Sternum
Humerus
Ribs
Lumbar Vertebrae
Radius
Pelvis
Coccyx
Ulna
Carpus
Metacarpus
Phalanges
Femur
Patella
Tibia
Fibula
Metatarsals
Tarsus
Phalanges
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Skeletal System

• Bones are divided into four classes based on
  their shape and function
• Long bones (support)
• Flat bones (muscle attachment and organ
  protection)
• Short bones (help in movement and change the
  direction of tendons)
• Irregular bones (vertebrae)

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Skeletal System

• Parts of the skeletal system protect vital
  organs.
• Skull (protects the brain)
• Rib cage (protects the heart, lungs, and certain
  abdominal organs)
• Vertebrae (protect the spinal column)