What are the parts of the skeletal system? The parts of the skeletal system include bones, cartilage, tendons, ligaments. What are the functions of the skeletal system? The functions of the skeletal system include, body shape, protects organs, levers for movement, mineral storage, blood cell formation. How are bones classified? Bones are classified by shape. Give some examples of bone classification Long bone: humerus, femur Short bone: trapezoid (wrist) Flat bone: sternum Irregular bone: vertabrae

What are the 3 parts of a long bone? The 3 parts of a long bone are the diaphysis, epiphysis, and epiphyseal plate (or line). Where is yellow marrow in a long bone? Yellow marrow is in the medullary cavity of a long bone. What is the periosteum? The periosteum is the outside covering of bone. What are some features of compact bone? Some features of compact bone include: location: diaphysis - tightly packed cells – Haversian systems – osteocytes – canaliculi (canals to connect bone cells) – lamellae (anchors bone cells).

What are some characteristics of spongy bone? Some characteristics of spongy bone include: location: epiphysis – made of trabeculae (gives it a “spongy” look – contains red marrow – lighter than compact bone

ARTICULATIONS (JOINTS) place where two bones meet 3 major types of joints 1. FIBROUS JOINTS little or no movement EX: sutures in skull (FONTANELS in babies) fontanels in babies close or OSSIFY in about 18 – 24 months

2. CARTILAGINOUS JOINTS bones held together by cartilage limited movement EX: cartilage between vertebrae – also between ribs & sternum

3. SYNOVIAL JOINTS freely movable parts of a synovial joint CARTILAGE – EX: meniscus in knee JOINT CAPSULE – forms joint cavity SYNOVIAL MEMBRANE– lines joint capsule – produces synovial fluid for lubrication LIGAMENTS– connect bone to bone

Types of Synovial Joints gliding joints EX: vertebrae, wrist

saddle joint EX: thumb

hinge joint EX: knee & elbow

pivot joint EX: neck, forearm

ball and socket joint EX: shoulder & hip

Openings, Projections, and Depressions in Bones (terminology) FORAMEN hole MEATUS tunnel or canal – nerves & blood vessels pass through PROCESS part of a bone that protrudes or sticks out SINUS cavities in cranium (skull bones)

Bone Ossification Ossification process of bone formation from cartilage 2 step process1. in an embryo, hyaline cartilage is covered with bone matrix bone building cells are called OSTEOBLASTS 2. The “enclosed” hyaline cartilage is digested away leaving a cavity inside the newly formed bone by birth most cartilage is converted to bone except for the articular cartilages and epiphyseal plates