14.2 Skeletal System

POINT > Identify five functions of the skeletal system POINT > Distinguish between axial and appendicular skeleton POINT > Describe the importance of joints POINT > Describe bone structure and growth POINT > Identify major bones

POINT > Identify five functions of the skeletal system 1. Movement: Skeletal system is where muscles attach. Muscles pull on bones to create movement

POINT > Identify five functions of the skeletal system 2. Shape and support: the backbone (vertebral column) is the main support center for the upper body Other bones attach to the backbone directly or indirectly Bones give shape to the body

POINT > Identify five functions of the skeletal system 3. Protection: The bones of your skull protect your brain. Your ribs protect your lungs and heart from injury

POINT > Identify five functions of the skeletal system 4. Produce blood cells: Red and white blood cells are formed by tissue called marrow, which is in the center of many large bones ~ 500,000,000,000 new blood cells every day!

POINT > Identify five functions of the skeletal system 5. Storage: Bones store minerals, especially calcium and phosphorus, for use by the body when needed

POINT > Distinguish between axial and appendicular Axial Skeleton: The axial skeleton includes the skull, vertebrae, ribs and sternum (blue) Appendicular Skeleton: The appendicular skeleton includes the appendages of the body, which are the shoulders, arms, hips, and legs (white)

CHECK: What are 5 functions of the skeletal system? What are two bones in the axial skeleton? What are two bones in the appendicular skeleton?

POINT > Describe the importance of joints Joints are places where bones come together Most joints are movable joints that allow the bones to move relative to each other (elbow, knee, hip, neck, etc.)

POINT > Describe the importance of joints Some joints are fixed joints that do not allow the bones to move relative to each other (skull and pelvic girdle)

POINT > Describe the importance of joints Ligaments are strong tissues that connect bone to bone and stabilize joints

POINT > Describe the importance of joints Cartilage is softer and more flexible than bone and cushions bones from striking or rubbing against each other

CHECK: What are joints? What are movable joints? What are fixed joints? What is a ligament? What is cartilage?

POINT > Describe bone structure and growth Bone is living tissue made up of cells Most bones have four layers: 1. Periosteum: Outer covering of bones 2. Compact Bone: Hard and dense 3. Spongy Bone: Softer, lies beneath the compact bone 4. Bone Marrow: Fills the gaps between the spongy bone

POINT > Describe bone structure and growth Bone is living tissue made up of cells

CHECK: What are 4 layers of bone? Which layer of bone is where blood cells are made?

POINT > Identify major bones of the body An adult human has ~ 206 bones The cranium (skull) is composed of 29 bones

POINT > Identify major bones of the body An adult human has ~ 206 bones The scapula (shoulder blade) connects the arm to the vertebral column

POINT > Identify major bones of the body The vertebral column has 26 vertebrae 1) The cervical region (neck bones) 2) The thorasic region (where the ribs attach) 3) The lumbar region (forms joints with the hips and legs)

POINT > Identify major bones of the body The pelvic girdle connects the legs to the vertebral column

POINT > Identify major bones of the body The sternum connects the ventral ribs to form a cage around the heart and lungs

POINT > Identify major bones of the body The humerus, radius and ulna are the bones of the arm

POINT > Identify major bones of the body The femur, tibia and fibula are the bones of the leg The femur is the largest and longest bone in the body

CHECK: What are 3 regions of the vertebral column? What are three leg bones? What is the cranium? What are three bones in the arm?

POINT > Describe bone structure and growth Osteoporosis is a disease that occurs as bones lose minerals (calcium) and become weak and brittle Women are more likely to get this as they age Good diet and exercise can prevent osteoporosis

POINT > Describe bone structure and growth Osteoporosis is a disease that occurs as bones lose minerals (calcium) and become weak and brittle

CHECK: What is osteoporosis? How can you prevent osteoporosis?

Homework: Read pages 474-481 Complete Study Guide Section Assessment page 481 GRAS 191-194