Experiment 3: Effects of Heat and Acid on Bone

As you have learned, bones are a key component in the strength and support of the body. Remarkably, bones are fairly light weight but can resist large amounts of stress. Within the bone, collagen fibers provide the strength and flexibility that bones need to handle the stress they bear. The hardness and firmness of the bone comes from mineral compounds. If these components are damaged, the structure of the bone will change. In this lab, you will examine the effect that excessive heat and acid have on the structure of bone.

Note: This lab requires FIVE days prep time for the acid and TWO hours prep time for the heat.

When working with raw chicken, be sure to wear gloves and wash all work surface with soap and water or a mild bleach solution when finished.

Procedure

1. Before beginning, be sure that all tissues have been removed from all chicken bones.
2. Begin by mixing 20 grams of salt with 40 grams of water. Mix thoroughly to create saline.
3. Pour 40 ml of the saline solution you created into the 5 x 8in bag and then place one of the chicken bone inside the bag. Seal the bag firmly and set it aside.
4. Next, pour 200 ml of vinegar into the 250 ml beaker.
5. Gently place one chicken bone into the vinegar solution. Cover the beaker with aluminum foil. Let this sit for five days.
6. Place the other chicken bone in a 5 x 8in bag without saline until it is needed.
7. On the fifth day, place the chicken bone in the 5 x 8in bag without saline onto a cookie sheet. Turn the oven on to 250?F.
8. Place this chicken bone into the oven for two hours. Always keep an eye on the oven while your chicken bone is being heated.
9. After two hours have elapsed, carefully pull the cookie sheet out of the oven using the hot pads. DO NOT touch the cookie sheet with your bare hands, it will be hot! Let the bone cool for five minutes.
10. While the heated bone is cooling, begin emptying the vinegar out of the beaker with the first bone. When the vinegar is removed, grab the chicken bone and place it on an underpad.
11. Remove the bone soaking in the saline solution, dry it and place it onto the underpad.
12. After five minutes, grab the chicken bone off the cookie sheet using the hot pads. Place it on the underpad next to the other two bones.
13. Gently try bending each of the three bone specimens. Notice the differences in the flexibility. Record your observations in Table 3 below.