The Skeletal System

What organs comprise the skeletal system?

Bones!

What are the functions of 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 Organ Organs are made of _____________.

A Bone is an Organ Organs are made of. Organs are made of tissues. Bones are made of: –Bone tissue –Connective tissue –Blood tissue

Bone Tissue bone cells) embedded in Osteocytes (bone cells) embedded in a hard made of: a hard matrix made of: Calcium salts (for strength) Collagen fibers (for flexibility)

Bone Tissue Bone tissue can have two appearances: CompactCompact SpongySpongy

Bone Tissue Where are the blood vessels in: Compact bone?Compact bone? Spongy bone?Spongy bone?

Bone Tissue Where are the blood vessels in: Compact bone!!!

Four Major Types of Bone Flat boneIrregular bone Long boneShort bone

Flat bone

Irregular bone

Long bone

Short bone

Bone Marrow Located inside Medullary Cavity. Two types: – –Red: makes blood cells – –Yellow: stores fat

Bone as a Storage Organ Fat is stored in yellow bone marrow.

Bone 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 Diet

Homeostasis of Calcium Extra calcium is stored in bone matrix. If body needs calcium, it is removed from bones.

Homeostasis of Calcium Extra calcium is stored in bone matrix. If body needs calcium, it is removed from bones.

Osteoporosis Most common in adults over 50. Cause: too little calcium. Result: – –Bone density decreases – –Easier to break bones Normal: Osteoporosis:

Osteoporosis

Osteoporosis 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 Cartilage Ligaments & Tendons Joints

Cartilage Made of: Cells Collagen fibers Matrix More flexible than bone. Located where bones connect.

Ligaments & Tendons Ligaments: Connective tissue: Collagen Some elastin Connect bone to bone Tendons: Connective tissue Connect bone to muscle

Joints (Articulations) Place where 2 or more bones come together. 3 types: – –Fixed joint – –Semimoveable joints – –Movable joints

Fibrous (Fixed) joints Little or no movement Best examples in the skull

Cartilaginous joints (Semimoveable) Some movement between bones can occur. Examples: Spine (intervertebral disk) Between pubic bones Ribs.

Synovial Joints (Movable) Allow for easy movement Synovial cavity contains synovial fluid (cushion) Cartilage covers bone surfaces.

Arthritis 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 Groups Skull Axial Skeleton Appendicular Skeleton

The Skull

The Axial Skeleton The Spine

The Axial Skeleton Ribs and Sternum

The Appendicular Skeleton Arm and Shoulder

The Appendicular Skeleton Leg and Pelvis

Name the major bones

Check Your Answers! 1)Mandible 2)Clavicle 3)Humerus 4)Pelvic girdle 5)Radius 6)Ulna 7)Phalanges 8)Cranium 9)Scapula 10)Ribs 11)Vertebral column 12)Carpals 13)Femur 14)Patella 15)Tibia 16)Fibula 17)Tarsals

Vocabulary 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