Premaxilla
Cranium
Carpometacarpus
2nd digit
1st digit
3rd digit
Mandible
(Dentary)
Cervical
Vertebrae
Radius
Humerus
Ulna
Sternum
Caudal
vertebrae
Ilium
Furculum
(fused
clavicles)
Sternum
Ischium
Pubis
/Femur
Fibula
Patella
Tibia (Tibiotarsus)
Tarsometatarsus
1st digit
Metatarsals
Phalanges
2nd digit
3rd digit
4th digit
Note: All photographs and text in this document are copyrighted by
Diane L. France
Additional exercises based upon the
Chicken Bone Exercise
Figure 1 Proximal epiphysis in cartilage
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 because 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?
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 immature 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.
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?
Does it make a difference in how much weight the chicken bone
can withstand before fracturing? 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.
Figures 3 and 4 Cinder block suspended from chicken bone
with 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 compression 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?
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 differences.