Structure and Movement Ch. 14

The Skeletal System Lesson 1

Functions of the Skeletal System Support Bones provide support for the rest of your body Movement Bones move because they are attached to muscles. Skeletal and Muscular System work together to move your body

Functions of the Skeletal Systems Protection Bones protect fragile tissues Brain, spinal cord, heart, lungs and others Production and Storage Bones produce Red Blood Cells Bones store fat and calcium When calcium is needed, it’s released from bones into your blood

Structure of Bones Compact Bone Tissue: Hard, outer portion Spongy Bone Tissue: Less dense Bone marrow: Soft tissue Red Marrow: Makes red blood cells Yellow Marrow: Stores fat

Structure of Bones Cartilage: A strong, flexible tissue that covers the end of bones Periosteum: Membrane that surround bone Growth Plate: Region that produces cartilages which is then replaced by bone

Joints A Joint is a place where two or more bones meet Joints enable a skeleton to move Bones are connected to other bones by tissues called ligaments When bones in joints move, ligaments stretch and keep bones from shifting away from each other Immovable Joints contain bones that connect but do not move Movable Joints allow for a wide range of motion

The Muscular System Lesson 2

Functions of the Muscular System Movement Stability Some muscles are attached to bone and cause movement of the body Other muscles are not attached to bone and cause blood and food to move Tendons attach muscle to bone Tendons work with muscles and keep joints in place when your body moves

Functions of the Muscular System Protection Temperature Regulation Muscles cover most of your skeleton and the organs inside your body Muscles act as a layer of padding Shivering is when muscles contract rapidly and change chemical energy into thermal energy Thermal energy helps to raise your body’s temperature

Skeletal Muscle Muscle that attaches to bone Voluntary Striated

Cardiac Muscle Found only in the Heart Involuntary Striated

Smooth Muscle Named for smooth appearance Helps move blood and food through body Involuntary Not Striated

Healthy Muscles and Homeostasis When you exercise, your cells need more oxygen and release more waste, such as CO2 The Cardiac muscles of your heart help maintain homeostasis by contracting more often (heart beating) As the heart contracts faster, the heart pumps more blood, and more O2 is carried to the cells Muscles benefit from a healthy diet and require energy to contract Exercise also helps keep muscles healthy Muscle cells decrease in size and strength without exercise Decreased size and strength can increase the risk of heart disease and bone injuries and make joints less stable