Dissecting a Chicken Leg Group Instructions- Readers –read to your group Procedure: 1. Remember that many animals have skeletal systems that are very similar to ours. Our leg is very much like that of a chicken leg including: femur (thigh bone) knee (hinge joint) fibula and tibia (smaller bones of the shin) cartilage ligaments These are all part of our skeletal system. Beyond that, we also have similar muscle structure, tendons, fat, and skin. We will be exploring each of these similar characteristics. 2. Place the chicken leg, skin side up, on the wax paper. Notice the texture of the skin. Note the follicles where feathers grew. 3. Turn the chicken leg over. The part of the chicken we call the meat is actually the muscle. Notice the yellow jelly-like substance which is fat. Pull off some of the fat and observe the difference in the consistency of muscle and fat.
Day 1 of Dissection Part 1: Examine the chicken. 1. Draw a picture of it. 2. Look closely at the skin. Can you see where the feathers once were? Draw evidence of this. 3. What function does the skin serve? 4. Remove the skin. The membrane that attaches the skin to the muscles is called ____________.
Procedure: 3. Locate the end of the bone that may be seen at either end of the leg. The cartilage is the white tissue that surrounds the end of the bone to protect it. The purpose of the cartilage is to keep bones from touching each other. It stops the wearing down of bone that would occur if the bones were in constant contact with each other. 4. Return the chicken leg to the skin up position. Pull the skin of the thigh back to show the underside of the skin. Locate the blood vessels of the skin. 5. Remove the remainder of the skin. Review the other tissue that is now visible (fat, muscle, cartilage, bone). 6. Pick up the leg and bend the joint. Notice it is a hinge joint because it only moves in one direction.
Procedure: 7. Using your blunt tools, carefully cut away some of the muscle to expose tendons (white areas of the muscle) that connect the muscle to the bone. Tendons are part of the muscular system. Tendons are near the ends of the bones. Ligaments are more difficult to locate. Ligaments attach the bones to other bones. Look around the joint and try to locate ligaments. Also expose the cartilage for viewing. The cartilage surrounds the bone where it would be touching another bone. Cartilage is the protective cushion between bones. 8. Carefully cut away the muscle, fat, tendons, and practice identifying the different parts of the muscular system.
Procedure: 9. Carefully break the hinge joint. Notice both parts of the hinge joint and how they fit together. Note the amount of cartilage protecting each part of the joint. Important points to remember: - cartilage is between bones - ligaments hold bone to bone - tendons hold muscle to bone 10. Carefully break the largest bone. Do not crush the bone. Observe the red jelly-like tissue inside the bone. Remember this is the bone marrow. Marrow produces red blood cells and platelets for use throughout our body. Red blood cells carry food and oxygen to all cells in our body. Platelets allow blood to clot rather than continue free flowing. Poke the marrow with the point of the scissors to show the consistency of the marrow.
Part 3. Remove the muscle bundles from the bone. A. The connective tissue that attaches muscles to bone is called _______________. B. What is the name of the connective tissue that covers the ends of the bone? ________________ C. After removing the muscles, you should see bones. Which bones do you see? _____________ _______________ ________________ D. Notice the hinge joint of the knee. Can you see the ball and socket joint, as well? _______________ E. Break the long bone. Examine the inside of the bone. Do you see the bone marrow? _________ Describe it F. What other systems have you observed in this chicken leg other than the skeletal system? You should be able to name at LEAST two more systems with examples of what you saw.
Procedure: 11. The skeletal system holds muscles in place, and in return the muscular system moves the skeletal system. The skeletal system makes red blood cells and platelets, and in return the circulatory system feeds the cells of the skeletal system. The skeletal system protects the lungs with ribs and in exchange, the respiratory system supplies oxygen to keep the cells of the skeletal system alive. The skeletal system protects the spinal column and brain, and in exchange, the nervous system keeps the entire body running correctly.
Dissecting a Chicken Leg Match the Vocabulary word to the correct definition: cartilage ligament tendon fat skin muscle blood vessel bone joint A). Fibers that contract and relax to effect body movement B). An elastic tube through which blood circulates. C). A tough, semi-rigid, calcified part of the skeleton D). connects two bones together. E). protective covering F). It covers the surface of joints, allowing bones to slide over one another, thus reducing friction and preventing damage. Keeps bones from touching one another. G). connects muscle to bone H). A point of connection between two movable parts I). is important in energy metabolism, heat insulation and cushioning. A yellow jelly-like substance. _____