The Skeletal The Skeletal SystemSystem
What organs comprise What organs comprise the skeletal system?the skeletal system?
What organs comprise What organs comprise the skeletal system?the skeletal system?
• Bones!
What are the functions of What are the functions of bones?bones?
• Support for the body• Movement
• Provide points of attachment for muscles
• Protect internal organs• Storage place for calcium and fat• Synthesis of blood cells
• house blood-producing cells
A Bone is an OrganA Bone is an Organ
Organs are made of _____________.Organs are made of _____________.
A Bone is an OrganA Bone is an Organ
Organs are made of Organs are made of tissues..
Bones are made of:Bones are made of:– Bone tissueBone tissue– Connective tissueConnective tissue– Blood tissueBlood tissue
Bone TissueBone Tissue
Osteocytes (bone cells) embedded inbone cells) embedded in
a hard a hard matrix made of: made of:• Calcium salts (for strength)• Collagen fibers (for flexibility)
Bone TissueBone Tissue
Bone tissue can have two appearances:
• CompactCompact• SpongySpongy
Bone TissueBone Tissue
Where are the blood vessels in:• Compact bone?Compact bone?• Spongy bone?Spongy bone?
Bone TissueBone Tissue
Where are the blood vessels in:
Compact bone!!!
Four Major Types of Four Major Types of BoneBone
• Flat bone Irregular bone• Long bone Short bone
Flat boneFlat bone
Irregular boneIrregular bone
Long boneLong bone
Short boneShort bone
Bone MarrowBone Marrow
• Located inside Medullary Cavity.• Two types:
– Red: makes blood cells– Yellow: stores fat
Bone as a Storage OrganBone as a Storage Organ
• Fat is stored in yellow bone marrow.
Bone as a Storage OrganBone as a Storage Organ
• Fat is stored in yellow bone marrow.• Calcium is stored in the matrix of
bone tissue.– Important for function of nerves &
muscles.– What kinds of food have lots of calcium?
Calcium in the DietCalcium in the Diet
Homeostasis of CalciumHomeostasis of Calcium
• Extra calcium is stored in bone matrix.
• If body needs calcium, it is removed from bones.
Homeostasis of CalciumHomeostasis of Calcium
• Extra calcium is stored in bone matrix.
• If body needs calcium, it is removed from bones.
OsteoporosisOsteoporosis• Most common in adults over 50.• Cause: too little calcium.• Result:
– Bone density decreases– Easier to break bones
Normal: Osteoporosis:
OsteoporosisOsteoporosis
OsteoporosisOsteoporosis• Most common in adults over 50.• Cause: too little calcium.• Result:
– Bone density decreases– Easier to break bones
• Prevention:– Get plenty of calcium in diet– Regular exercise
Accessory Structures Accessory Structures
•Cartilage
•Ligaments & Tendons
•Joints
CartilageCartilage•Made of:
•Cells
•Collagen fibers
•Matrix
•More flexible than bone.
•Located where bones connect.
Ligaments & TendonsLigaments & Tendons•Ligaments:
•Connective tissue:
•Collagen
•Some elastin
•Connect bone to bone
•Tendons:
•Connective tissue
•Connect bone to
muscle
Joints (Articulations)Joints (Articulations)
• Place where 2 or more bones come together.
• 3 types:– Fixed joint– Semimoveable joints– Movable joints
Fibrous (Fixed) jointsFibrous (Fixed) joints
•Little or no movement
•Best examples in the skull
Cartilaginous jointsCartilaginous joints (Semimoveable) (Semimoveable)
•Some movement between bones can occur.
•Examples:
•Spine (intervertebral disk)
•Between pubic bones
•Ribs.
Synovial JointsSynovial Joints(Movable)(Movable)
•Allow for easy movement
•Synovial cavity contains synovial fluid (cushion)
•Cartilage covers bone surfaces.
ArthritisArthritis• Arthro = joint -itis = inflammation• Osteoarthritis
– Cartilage wears down– Movement is painful– People over 60 years old
• Rheumatoid Arthritis– Synovial fluid builds up in cavity– Autoimmune (body attacks itself)– Can occur at any age
Bone Bone GroupsGroups
•Skull
•Axial Skeleton
•Appendicular Skeleton
The SkullThe Skull
The Axial SkeletonThe Axial SkeletonThe Spine
The Axial SkeletonThe Axial Skeleton
Ribs and Sternum
The Appendicular The Appendicular SkeletonSkeleton
Arm and Shoulder
The Appendicular The Appendicular SkeletonSkeleton
Leg and Pelvis
Name the major bonesName the major bones
Check Check Your Your AnswerAnswers!s!
1) Mandible2) Clavicle3) Humerus4) Pelvic girdle5) Radius6) Ulna7) Phalanges8) Cranium9) Scapula10) Ribs11) Vertebral column12) Carpals13) Femur14) Patella15) Tibia16) Fibula17) Tarsals
VocabularyVocabulary
• Skeleton• Axial skeleton• Appendicular skeleton• Periosteum• Compact bone• Haversian canal• Osteocyte• Spongy bone• Bone Marrow• Fracture• Diaphysis
• Ossification• Epiphyseal plate• Joint• Fibrous joint• Cartilaginous joint• Synovial joint• Ligament• Synovial fluid• Rheumatoid arthritis• Osteoarthritis