1. The musculoskeletal system Dr. T.

2. Why are we looking at these two systems together? It is because these two systems work together so closely. It is because these two systems work together so closely. The skeletal system gives us our shape, supports our bodies, protects vital organs, and is a reservoir of important minerals. The skeletal system gives us our shape, supports our bodies, protects vital organs, and is a reservoir of important minerals. Muscles provide us with the power that allows us to move around. Muscles provide us with the power that allows us to move around. Without a skeletal system to provide support, our muscles could not function! Without a skeletal system to provide support, our muscles could not function!

3. Components of the Musculoskeletal system 1. Bones 2. Cartilage 3. Ligaments 4. Tendons 5. Skeletal (Striated) muscles. Note: There are two other types of muscle tissue we will learn about, but they are not considered part of the musculoskeletal system. Note: There are two other types of muscle tissue we will learn about, but they are not considered part of the musculoskeletal system.

4. What are muscles? Muscles consist of cells and contractile fibers. Muscles consist of cells and contractile fibers. Muscle work by shortening in length. Muscle work by shortening in length. You have two sets(or more) of muscles attached to many of your bones which allow them to move. You have two sets(or more) of muscles attached to many of your bones which allow them to move. There are 630 active muscles in your body. There are 630 active muscles in your body. Muscles can only pull, they can’t push. Muscles can only pull, they can’t push.

5. More on muscles. The Three Types of Muscles Type of Muscle Smooth Muscle Cardiac Muscle Skeletal Muscle AppearanceSmoothStriatedStriated Voluntary or InvoluntaryInvoluntaryInvoluntaryVoluntary FunctionControls Controls Moves bones. movement ofcontractionsWork in pairs. internal organsof the heartWhen one contracts the other relaxes. Attached to bones by tendons.

6. Check for learning. On the paper provided, answer the following questions without referring to your worksheet. On the paper provided, answer the following questions without referring to your worksheet. 1. What are the 5 components of the musculo-skeletal system? 1. What are the 5 components of the musculo-skeletal system? 2. What are the 3 types of muscle tissue? 2. What are the 3 types of muscle tissue?

7. Bones Like everything else in your body, your bones consist of cells. Like everything else in your body, your bones consist of cells. Two types. Two types. Osteoblasts: Cells which build bones. Osteoblasts: Cells which build bones. Osteoclasts: Cells which break down bones Osteoclasts: Cells which break down bones To release minerals, like calcium To release minerals, like calcium How to remember the difference? OsteoBlasts Build Bone. 3 B’s.

8. Thanks for your support. Without a bones you’d be floppy like a beanbag. Without a bones you’d be floppy like a beanbag. Could you stand up? Forget about it. Could you stand up? Forget about it. Could you walk? No way, man! Could you walk? No way, man! Without bones you’d be a puddle of skin and guts on the floor. Without bones you’d be a puddle of skin and guts on the floor.

9. The job of the bones. Your skeleton has several jobs. Your skeleton has several jobs. Some bones, like your backbone, provide structure. Some bones, like your backbone, provide structure. Other bones, like your skull and rib cage protect vital organs. Other bones, like your skull and rib cage protect vital organs. The tiniest bones in your body, in the inner ear, help to transmit sound waves to your brain. The tiniest bones in your body, in the inner ear, help to transmit sound waves to your brain.

10. So how many bones do we have? Actually, you have less than you once did. Actually, you have less than you once did. As a new born, you had over 300 bones. As a new born, you had over 300 bones. As you grew up, many of these bones fused together. As you grew up, many of these bones fused together. You now have 206 elegant bones in your body. You now have 206 elegant bones in your body.

11. So how do muscles and bones do their jobs? With a lot of help. With a lot of help. Along with muscles and bones, you need joints. Along with muscles and bones, you need joints. Joint provided flexible connections between bones. Joints are primarily made up of tissue called ligaments. Joint provided flexible connections between bones. Joints are primarily made up of tissue called ligaments. Tendons attach bone to muscle, ligaments attach bone to bone. Tendons attach bone to muscle, ligaments attach bone to bone.

12. Types of joints Hinge joints: Like in your knee, enable bones to move back and forth. Hinge joints: Like in your knee, enable bones to move back and forth. Pivot joints: Like in your neck, enable you to turn your head around. Pivot joints: Like in your neck, enable you to turn your head around. Ball and socket joints: Like in your shoulder, enable you to move your arms 360 degrees. Ball and socket joints: Like in your shoulder, enable you to move your arms 360 degrees. Semi-moveable joints: Like the ones between the vertebrae in your backbone. Semi-moveable joints: Like the ones between the vertebrae in your backbone.

13. Are bones alive? Absolutely. If not, then broken arms and legs would never heal. Absolutely. If not, then broken arms and legs would never heal. Like all other cells in your body, bone cells need nutrients and oxygen and they produce wastes. Like all other cells in your body, bone cells need nutrients and oxygen and they produce wastes. When you break a bone, blood clots form to close the space between the two segements. Osteoblasts the begin the process of depositing bone to heal the fracture. When you break a bone, blood clots form to close the space between the two segements. Osteoblasts the begin the process of depositing bone to heal the fracture.

14. What is bone marrow? Many of your larger bones are hollow. Many of your larger bones are hollow. Being hollow helps to reduce the weight of your bones. Being hollow helps to reduce the weight of your bones. In the center of these bones, bone marrow makes new red and white blood cells. In the center of these bones, bone marrow makes new red and white blood cells. So it turns out that your bones actually make blood! How cool is that? So it turns out that your bones actually make blood! How cool is that?

15. Fun bone facts The human hand has 27 bones, your face has 14 The human hand has 27 bones, your face has 14 The longest bone in your body is your femur, ¼ your height. The longest bone in your body is your femur, ¼ your height. Humans and Giraffes have the same number of bones in their necks. Humans and Giraffes have the same number of bones in their necks.

16. Check for learning II On your answer sheet, answer the following questions. Do not refer to your worksheet. On your answer sheet, answer the following questions. Do not refer to your worksheet. 3. How many different types of bone cells are there? 4. List three functions of your bones. 5. How many bones does a newborn baby have? How many bones do you have?