Introduction.


Today I am going to dissect a chicken leg. The purpose of my lab is to become more familiar with tissue, bones, and tendons. Seeing how muscles attach to bones and tendons is another important part of this lesson.
Procedure:

Put on gloves, if you have them.

2. Thoroughly rinse and dry one chicken leg. Place it on a plate or tray.

3. Examine the outside skin tissue.

4. Using scissors and a sharp knife, begin to work slowly and carefully to cut the skin and peel it away from the muscle below. Notice the clear connective tissue that holds the skin to the muscles. As you peel off the skin, you may need to cut away some of this connective tissue. Work slowly and carefully with scissors and knife until all skin is removed.

5. Connective tissue appearance.

A. Describe the appearance of the connective tissue.
The tissue was gelatinous, tough, and stretchy. It was mostly white or light in color.

B. What type of connective tissue is this? Epithelial Tissue.

6. Observe the yellowish clumps of fat tissue found outside the skin.

A. Describe the fat. The fat was slightly yellow in color and soft to the touch.

B. What are at least two of its functions? Two of the functions of fats are store energy and insulation.

C. Give the biological rem for the type of cells that store fat. Lipids

7. Observe bundles of pale, pink muscle tissue surrounding the bones.

8. Observe, with your naked eye, bundles of muscle tissue surrounding the bones. Separate the bundles of muscle by separating them out with your fingers. Begin by Inserting your thumb in to the muscle of the lower leg. You will need to push forcefully through the connective tissue covering the muscle, but it will give way at the natural separations between the muscle bundles.

Continue separating the muscle by forcing your thumb and fingers through the muscle until you are able to distinguish several separate bundles.

A. Describe the arrangement of the muscle bundles. The bundles of muscle were almost stacked on one another.

B. Do you see just one muscle, or are there many muscles present? There are several muscles.

C. How can you tell? They are kind of outlined and you can see them stacked on each other. Also you can see different tendons attached to different muscles.

9. The strong, shiny, white cords, called tendons, hold the muscle to the bones. Some of these tendons will pull away from the bone as you separate the muscle bundles.

Find the tendons of the chicken leg. Using the dissection scissors, cut across the tendons at Line A. Observe the numerous tendons and pull the freed muscles down and away from the bone, as if you were peeling a banana. Be careful you don’t cut any ligaments that attach bone to bone. Look closely at the ligaments.

Examine the two bones in the lower leg. The large bone (Bone A) is the tibia. The small, toothpick-like bone (Bone B) is the fibula.

A. What sort of connective tissue are tendons composed of? Tendons are fibrous connective tissue composed of collagen.

10. Skeleton Muscle function.

A. What are skeletal muscles? Skeletal muscles are attached to bones.

B. What are their functions? Muscles are responsible for movement of the body.

11. Remove a single muscle by cutting the tendons and peeling the muscle away from the bone. Nerves are generally thin, threadlike, white strands found between the muscle and the nearest bone. Look for the nerve in your specimen. The texture is much different from a tendon or bone. It is rather slippery.

A. Did you find it? Yup

12. Remove the muscle that covers Join B by cutting parallel to the femur, up ward toward the backbone. Remove pink muscle tissue until you see a shiny white sheet of ligament that cover the joint. Present is an exterior ligament that hips the femur in the hip socket.

A. What type of connective tissue compose the ligaments? Ligaments are fibrous tissue

13. Remove all remaining muscle to expose the bones of the chicken leg.

14. Cut onto the hinge joint by cutting into the top of the covering of the joint from the femur side. It will become apparent that you must remove the kneecap are to expose the menisci and ligaments within. Pull up on the kneecap are and cut through it with the scissors. You will have cut through the bursa, a sax that acts as a shock absorber for the knee joint. These are found in every joint.

15. Pull the covering back and look into the inside of the joint. You will see more white bands of ligaments holding the bones together. Observe the shiny, white layer covering the ends of the bones is cartilage. It helps the bones slide smoothly when the leg bends.

16. Bend the specimen at Join B and rotate the femur in all directions. Refer to pages 113-115 in your text book and answer these questions.

A. What type of joint is this? A ball and socket joint also known as a synovial joint
B. What type of movement is being demonstrated? The synovial joint is able to move by bending, extending, and rocking back and forth.

17.  Cut the ligaments at the joint between the upper and lower leg. Examine how the bones fit into each other.

A. Describe the texture of the ends of the bones at the joint.
The texture at the ends of the bones is very smooth.

B. What is the specific name of this type of connective tissue? Hyaline Tissue.

C. What occurs when the cartilage at joints wears away? Arthritis.

D. How is a joint of this type built to delay this event? The joint has many protective layers such as muscles and tendons. The join itself is surrounded by a liquid to help mobility.

18. DO NOT BREAK THE RAW CHICKEN BONE. THERE IS DANGER FROM BONE FRAGMENTS FLYING OUT. If you could see inside the bone

A. What soft material would you find? Bone Marrow

B. Name three specific types of cells present here. We will not break it open. Osteoblast, osteocyte, and osteoclast.

C. Name three functions of bone. Bones produce blood cells that nourish the body. Bones provide support for the body. They also serve as storage for minerals such as calcium and phosphorous.

19. Explore and examine all the parts before cleaning the area.

20. Dispose of materials as directed. Using warm water and soap thoroughly wash all tools and materials, including your hands and the surface you worked upon.