Ulna

RadiusCervical Vertebrae

/Femur

Tibia (Tibiotarsus)

FibulaSternum

Furculum (fused clavicles)

Tarsometatarsus

Metatarsals

1st digit

2nd digit

3rd digit4th digit

Phalanges

Pubis

Patella

Ischium

1st digit

Carpometacarpus

Humerus

2nd digit

3rd digit

CraniumPremaxilla

Mandible (Dentary)

SternumIlium

Caudal vertebrae

Note: All photographs and text in this document are copyrighted by Diane L. France

Additional exercises based upon the Chicken Bone Exercise

Growth and Development

In the text, you removed the cartilage from the proximal end of the drumstick (tibia and fibula). When exposed to a backlight, you can see the small epiphysis embedded in the cartilage.

1. Remove the distal cartilage (it is a little more difficult sometimes be-cause it is often overcooked).

How many epiphyses can you find?

2. Perform a blunt dissection on a chicken wing (if you get barbecued wings or “hot wings” notice that there are two different kinds of wing type: the meatier portion and the thinner portion).

What bones are represented in the cooked chicken wing? Identify each one of the three bones.

Remove the cartilage ends and look for epiphyses. How many do you see?

Figure 1 Proximal epiphysis in cartilage

3. Dissect a roasting chicken (the chicken we have been dissecting to this point have been frying chickens). What differences do you see in the muscles in a roasting chicken drumstick when compared to the frying chicken?

4. Dissect a turkey drumstick and inspect the muscles, tendons, cartilage and bone. What similarities do you see?

What differences do you see?

Do you find epiphyses? If so, describe their size relative to the size of the cartilage matrix (compared to the chickens). 5. Most of our food meat that we buy at the grocery store is from imma-ture animals. Ham hocks, lamb, beef, etc., etc. should all have epiphyses, although you have to choose the cut carefully.

If you have a meal of any mammal where you are near an articular surface, check the epiphyseal surfaces and identify the bone you are examining.

What does the epiphyseal surface look like? Is it similar or very different from the chicken and turkey surfaces? (this is one of the ways we determine species).

Figure 2 Pig forelimb (“hand”). Arrows indicate epiphyseal lines

Organic and Inorganic Components in Bone

In the text, you explored the basic muscle and bone elements of a fried chicken leg, and in doing so you identified some basics of muscle and bone anatomy in a bird’s lower leg. The next step in our exercise is to explore the organic and inorganic components of bone.

6. Soak the chicken bone in vinegar for about two to three weeks.

What do you notice about the chicken bone after that period of time?

7. Fresh bone consists of an organic and an inorganic component.

Is what you see the organic or the inorganic component? How do you know? What, specifically, did the vinegar do to the bone?

The organic component of bone allows it to respond to blunt trauma by bending until it reaches its elastic limit, at which time it finally fails and fractures.

Repeat the experiment and strap the chicken bone to the weights with a wire. Does it make a difference in how much weight the chicken bone can withstand before fracturing? Why?

Describe the fracture patterns in the chicken bone with the zip-tie and with the wire. How do they differ? Why?

Trying freezing the bone before repeating this experiment. Does it withstand more, less, or the same weight? Why?

Figures 3 and 4 are photographs of a chicken tibia holding up a cinder block that weighs 24 pounds. This tibia was from a fried chicken leg (i.e. cooked). The tibia is strapped to the cinder block by a standard plastic zip-tie.

8. Try this experiment and keep adding weight (it doesn’t have to be a cinder block) until you reach the elastic limit of the chicken bone and it fractures. Mark the upper side of the chicken bone with a magic marker. How much weight did the bone withstand?

Repeat this experiment with a different chicken bone. Did it withstand the same weight?

9. This chicken bone was tapped with a hammer in the direction indicated by the arrow. In Chapter 14, you learned that bone withstands compres-sion forces better than it withstands tension forces.

Figure 5 Chicken bone tapped with hammer

Are the compression forces on the top of this bone or the bottom?

Figures 3 and 4 Cinder block suspended from chicken bone with zip tie

Mark a point at midshaft on a chicken bone with a magic marker and then tap that point with a hammer or other instrument. Was the fracture pattern similar to the photograph shown above?

Do you have the same fracture pattern if the bone is frozen?

Hit either end of the cooked chicken bone with a hammer. How does the fracture pattern differ from that in midshaft? Why?

Do you have the same fracture patterns if the bone is raw? Be careful with raw chicken - use safe food handling methods!!

10. Place the chicken bone on a table so that it is lying flat (the bone is curved, so if you put it on the table on one side, it will lie flat. Crush the bone with a heavy object (experiment with different objects). What fracture patterns do you see? Why are they different?

11. Repeat these experiments with a turkey drumstick. How do the patterns differ?

12. If you have mammal bones from the growth and development section, repeat these trauma exercises with those bones and describe the differ-ences.