Skeletal System

Annotations:

• •5 levels of human body organization: Cells Tissues Organs Organ systems Organisms
• Homeostasis is the tendency toward keeping the internal balance of the human body
• It is important for the human body to maintain homeostasis because it will keep the internal balance of the body stable in response to external conditions
• Bones are hard Cartilage is more flexible and covers articular surfaces
• •More protein:Cartilage~Elasticity/Softness •More calcium:Bone~Stored/Harder
• Ligaments are strong elastic tissues that connect bones to other bones (On the sides of bones) Cartilage is a strong,flexible tissue that covers and protects the ends of bones,soft,smooth,doesn't contain blood vessels
• Function of skeletal system: 1)Supports the body 2)Made up of bone,cartilage,ligaments 3)Protects internal organs 4)Allows movement 5)Axial/Appendicular
• Axial: Skull-Hips (Skull,Spine,Ribs,Sternum,Coccyx) Appendicular: (Arms[Humerus],Legs[Femur],Pelvis)
• Skull: Protects brain Spine: Protects spinal cord Ribs{12 pairs-2 floating}Protect lungs,heart,and other chest organs
• Sternum-Breast bone Vertebrae-Small cylindrical bones with a central hole through which the spinal cord passes
• Types of bone tissue: •Compact: Hard,Dense,Living,Supplies bone with nutrients •Spongy: Lightweight,Holes,Strong ~Spongy:- Yellow marrow:Stores fat Red marrow:Produces new blood cells
• Cartilage Role: 1)Covers and protects the end of bones 2)Gives shape to some parts of the body 3)Holds open the trachea 4)Forms outer part of ear 5)Tip of nose
• •Osteogenesis:Bone formation •Ossification:Cartilage cells replaced by bone cells, calcium is deposited in protein matrix of cartilage •Osteoporosis:Progressive bone disorder,characterized by a decrease in bone mass and mineral density (Bone formation
• Joint: Location where bones come together 1)Hinge~Forward and backward 2)Ball-and-Socket~All directions 3)Pivot~Rotational at 2 ends 4)Gliding~Slides in any direction H:Elbow/Knee BAS:Shoulder/Hip P:Skull/Spine G:Ankle/Wrist
• Injuries: •Fracture:-Break in bones •Dislocation:-Injury to joints,Ends of bones move out of their original positions forcefully •Sprain:-Occurs when ligaments in joints stretch too far and tear F:Traumatic injury/Medical condition (Bone cancer,Osteoporosis) D:Shoulder-Humerus out of scapula S:Mainly in ankle and wrist,Causes swelling