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Dissecting a Chicken Leg
Birgit Self 4/13/09 TWU EDUC 5131
Dissecting a Chicken Leg
Activity Instructions
Purpose:
The purpose of this activity is to make students aware of the elements of the
skeletal system and how they interrelate.
Materials:
• Raw chicken leg quarter - one for each 2 student team
• Plastic knives and forks – one set per student
• Latex gloves for each student
• Copies of these activity instructions – one per student
• Wax paper, about 2 X 2 foot square – one per team
Birgit Self 4/13/09 TWU EDUC 5131
Dissecting a Chicken Leg
Background Information:
A bone is a kind of body tissue which is made of both living and nonliving
material. Each human body contains 206 different bones. All of the bones in the
body, together with the tissues that bind them and protect them form the skeletal
system. Each bone is made up of several different parts. A typical long bone is
enlarged at both ends with a shaft in between.
A membrane called the periosteum covers the bone. Under that layer is compact
bone. Beneath the compact bone is a material called spongy bone. Spongy bone
is softer than compact bone and contains many hollow spaces. These spaces
help prevent the bone from breaking, because they act as shock absorbers when
the bone is hit or banged. It is most of the material at the ends of long bones.
Inside the shaft is a soft tissue called marrow, where the body's blood cells are
produced. There are two types of marrow: yellow marrow and red marrow. It is
the red marrow that produces red blood cells, white blood cells and platelets.
Just like other living tissues in the body, the bones must be supplied with blood
or they will die.
Dissecting
a Chicken Leg
Background Information:
The skeletal system has five very
important jobs. Support, protection,
movement, storage, and production
of blood cells. Just think, if we did
not have a skeletal system we
would be just like a blob of Jell-O.
The bones also protect many
organs, and also the brain. Our
skull protects the brain and our ribs
protect our internal organs.
Dissecting a Chicken Leg
Background Information:
The place where bones are connected is called a joint. Joints give you the
freedom to move your body. A skeleton without joints would be like a statue.
There are several different types of joints in our body. The hinge joint (knee,
elbow, fingers) works like a door's hinge. It only allows movement only in one
plane. The ball and socket joint (hip, shoulder) allows a great range of
movement in all directions. The pivot joint (neck) moves around in a back and
forth motion. A globe rotating is a good example of this. The gliding joint (wrist,
ankle) allows a great range of motion. This joint is connected by one bone
sliding over another bone. Finally, fixed joints (skull, pelvis) do not move at all.
All of these joints are crucial to the proper functioning of the body.
Dissecting a Chicken Leg
Different Joints:
1. Ball &
Socket joint
2. Ellipsoid joint
3. Saddle Joint
4. Hinge Joint
5. Pivot Joint
Dissecting a Chicken Leg
Lab Goals:
Lab Goals:
1. To observe scientifically the shape, color, and properties of Muscle, Skin,
Ligament, (Tendons) and Cartilage Tissue.
2. To record how the tissues are attached together to make a moveable joint, like
the knee joint
Dissection Drawing:
Dissecting a Chicken Leg
Group Instructions
Procedure:
1. Many animals have skeletal systems that are very similar to ours.
Our leg is very much like that of a chicken leg including:
•
•
•
•
•
femur (thigh bone)
knee (hinge joint)
fibula and tibia (smaller bones of the shin)
cartilage
ligaments
These are all part of our skeletal system. Beyond that, we also have
similar muscle structure, tendons, fat, and skin. We will be exploring each of
these similar characteristics.
2. Place the chicken leg, skin side up, on the wax paper. Notice the
texture of the skin. Note the follicles where feathers grew.
3. Turn the chicken leg over. The part of the chicken we call the meat is
actually the muscle. Notice the yellow jelly-like substance which is fat.
Pull off some of the fat and observe the difference in the consistency of
muscle and fat.
Dissecting a Chicken Leg
Group Instructions
Procedure:
3. (continued) Locate the end of the bone that may be seen at either end of
the leg. The cartilage is the white tissue that surrounds the end of the
bone to protect it. The purpose of the cartilage is to keep bones from
touching each other. It stops the wearing down of bone that would occur
if the bones were in constant contact with each other. [see photo #1]
4. Return the chicken leg to the skin up position. Pull the skin of the thigh
back to show the underside of the skin. Locate the blood vessels of the
skin. [photo #2]
5. Remove the remainder of the skin. Review the other tissue that is now
visible (fat, muscle, cartilage, bone). [photo #2]
6. Pick up the leg and bend the joint. Notice it is a hinge joint because it
only moves in one direction. [photo #1]
Dissecting a Chicken Leg
Group Instructions
Procedure:
7. Using your plastic knives and forks, carefully cut away some of the muscle
to expose tendons (white areas of the muscle) that connect the muscle to
the bone. Tendons are part of the muscular system. Tendons are near the
ends of the bones. Ligaments are more difficult to locate. Ligaments attach
the bones to other bones. Look around the joint and try to locate ligaments.
Also expose the cartilage for viewing. The cartilage surrounds
the bone where it would be touching another bone. Cartilage is the
protective cushion between bones.
8. Carefully cut away the muscle, fat, tendons, and practice identifying the
different parts of the muscular system.
Dissecting a Chicken Leg
Group Instructions
Procedure: (This part is optional for student - Mrs. Self will demonstrate)
9. Carefully break the hinge joint. Notice both parts of the hinge joint and how they
fit together. Note the amount of cartilage protecting each part of the joint.
Important points to remember:
- cartilage is between bones
- ligaments hold bone to bone
- tendons hold muscle to bone [see photo #5]
10. Carefully break the largest bone. Do not crush the bone. Observe the red
jelly-like tissue inside the bone. This is the bone marrow. Marrow produces red
blood cells and platelets for use throughout our body. Red blood cells carry food
and oxygen to all cells in our body. Platelets allow blood to clot rather than
continue free flowing. Poke the marrow with the point of the scissors to show
the consistency of the marrow. Also note how brittle the one is and how easily
it can be broken. Your own bones can break this easily too. [photo # 6]
Dissecting a Chicken Leg
Group Instructions
Procedure:
11. The skeletal system holds muscles in place, and in return the muscular system
moves the skeletal system. The skeletal system makes red blood cells and platelets,
and in return the circulatory system feeds the cells of the skeletal system. The skeletal
system protects the lungs with ribs and in exchange, the respiratory system supplies
oxygen to keep the cells of the skeletal system alive. The skeletal system protects the
spinal column and brain, and in exchange, the nervous system keeps the entire body
running correctly.
Because muscles are so important to any animal, they are incredibly complex. They
are efficient at turning fuel into motion, they are long-lasting, they are self-healing
and they are able to grow stronger with practice. They do everything from allowing
you to walk to keeping your blood flowing!
Dissecting a Chicken Leg
Group Instructions
Photo #1:
Dissecting a Chicken Leg
Group Instructions
Photo #2:
Dissecting a Chicken Leg
Group Instructions
Photo #3:
Dissecting a Chicken Leg
Group Instructions
Photo #4:
Dissecting a Chicken Leg
Group Instructions
Photo #5:
Dissecting a Chicken Leg
Group Instructions
Photo #6:
Dissecting a Chicken Leg
Vocabulary Words:
muscle
A). Fibers that contract and relax to effect body movement
blood vessel
B). An elastic tube through which blood circulates.
bone
C). A tough, semi-rigid, calcified part of the skeleton
ligaments
D). connects two bones together.
skin
E). protective covering
cartilage
F). It covers the surface of joints, allowing bones to slide over
one another, thus reducing friction and preventing damage.
Keeps bones from touching one another.
tendons
G). connects muscle to bone
joint
H). A point of connection between two movable parts
fat
I). is important in energy metabolism, heat insulation and
cushioning. A yellow jelly-like substance.
Dissecting a Chicken Leg
Vocabulary Words:
Periosteum
A dense layer of vascular connective tissue enveloping the bones
except at the surfaces of the joints
Solid bone
The layer of bone between the periosteum and spongy bone
Spongy bone
Femur
Is softer than compact bone and contains many hollow spaces
The thigh bone or upper hind limb on animals
Tibia
The inner and typically larger of the two bones between the knee and
the ankle
Hinge joint
A bone joint in which the only movement allowed is forward and
backward.
Ball and socket
joint
A joint, such as the hip joint, that is partly a sphere shape, it lies in a
socket, allowing movement in many directions and rotates.
Connective
tissue
A tissue that connects, supports, binds, or separates tissues or organs.
Epithelial tissue
Cells that line the cavities and surfaces of structures in the body.
Dissecting a Chicken Leg
Check for Understanding
Match the Vocabulary word to the correct definition:
_____ cartilage
A). Fibers that contract and relax to effect body movement
_____ ligament
B). An elastic tube through which blood circulates.
_____ tendon
C). A tough, semi-rigid, calcified part of the skeleton
_____ fat
D). connects two bones together.
E). protective covering
_____ skin
_____ muscle
F). It covers the surface of joints, allowing bones to slide over
one another, thus reducing friction and preventing damage.
Keeps bones from touching one another.
_____ blood vessel
G). connects muscle to bone
_____ bone
H). A point of connection between two movable parts
_____ joint
I). is important in energy metabolism, heat insulation and
cushioning. A yellow jelly-like substance.
Dissecting a Chicken Leg
Additional Information and Resources:
Hyperlinks for Additional Information:
How to dissect a chicken leg
Four Types of Tissues
Video of a Chicken Leg Dissection