The skeletal system is made up of cartilage and bone. Both bone and cartilage are connective tissues, that is, they are composed of cells in a matrix with intracellular fibers. Just imagine connective tissue as a gelatin salad with grapes and coconut. The grapes would represent cells, the gelatin the support material for matrix, and the pieces of coconut the intracellular fibers. By changing the amounts of each ingredient and adding extra substances, we can produce a material that is very hard like bone and can withstand weight or softer like cartilage which can be used as a cushioning material.
In this exercise, we will examine a fresh raw chicken bone to study bone structure.
Note: To complete both experiments, you will need two raw chicken bones. Each experiment requires a separate bone.
Fresh chicken leg bone
1. Carefully remove the skin and muscles from the bone as you do this, note the way that muscles are attached..
2. Split the bone lengthwise.
3. Examine the bone and locate the following structures: a. Tendon – Examine the attachment of the muscles to bone. In most cases, the long ropelike attachment is a tendon and is composed of dense regular connective tissue. b. Periosteum This thin membrane covers the outside of the bone. c. Articular cartilage Note this thin layer of cartilage covering the epiphysis. d. Marrow cavity This hollow cavity in the diaphysis of the bone is lines with a thin membrane called the endosteum. e. Spongy bone This type of bone is located in the ends or epiphyses of the bone and appears to be open with small spicules or bars. f. Compact bone Makes up the shaft or diaphysis of the bone.
1. How does spongy bone differ from compact bone? What differences did you see in the appearance of the spongy bone and compact bone? What color was the spongy bone?
2. How does cartilage differ from bone? How did each one feel when pierced with the knife?
3. How did the periosteum and endosteum differ in thickness?
4. Was the bone marrow yellow, red, green or blue?
5. What type of cartilage makes up the articular cartilage?
6. How did the articular cartilage differ in appearance from the spongy bone?
7. What color was the tendon? What substance gives it strength?
8. How did the raw bone differ in appearance from the baked bone in the other experiment?
Note: Chicken may be contaminated with Salmonella. Wear gloves when possible during handling and wash hands thoroughly at the conclusion of your work!!
Note: There are questions that will tell me if you did the dissection as I asked. If you miss these questions, you will receive no credit for the dissection.