SKELETAL SYSTEM Section 1
WARM-UP Answer the following questions to the best of your ability…. 1. How many bones are in the human body? Does that number ever change? 2. Why do we have bones? 3. Are bones alive? 4. What makes up your Skeletal System?
Skeletal System Made up of all the bones and cartilage in your body Has 5 major functions: Gives shape and support to your body Protect internal organs Major muscles are attached to your bones Blood cells are formed in the marrow of your bones (center) Calcium and Phosphorus compounds are stored in your bones for later use
DISCOVERY EDUCATION
Bone Structure PERIOSTEUM COMPACT BONE SPONGY BONE
CARTILAGE Acts as a SHOCK ABSORBER REDUCES FRICTION between bones when they rub together NO CARTILAGE= PAIN!!!
Before birth, your Skeletal system was ALL CARTILAGE It gradually is replaced by bone…the Skeletal System you were born with
Osteoblasts- Build bone with Calcium and Phosphorus, which make it hard Osteoclasts-Break down bone tissue If you don’t use it, you loose it!!!
Joints Any place where two bones come together
Types of Movable Joints
Pivot Joint One bone rotates in a ring of a stationary bone Ex. Turning your head
Ball and Socket Joint The rounded end of one bone fits into a cuplike cavity on another bone Ex. Shoulder/hip
Hinge Joint Back-and-forth movement Ex. Elbows, Knees, Fingers
Gliding Joint One part of the bone slides over another one Ex. Wrists, Ankles, Between Vertebrae Used the MOST in the body
IMMOVABLE JOINTS Allow little to NO movement Ex. The joints of the bones in your skull, pelvis, and vertebrae
5 gliding
How many bones are in the human body? 206 Does that number ever change? YES
Why do we have bones? Gives shape and support to your body Protect internal organs Major muscles are attached to your bones Blood cells are formed in the marrow of your bones (center) Calcium and Phosphorus compounds are stored in your bones for later use
Are bones alive? YES
What makes up your Skeletal System? Bones and Cartilage