You might have to cut some of the connective tissue to help the skin separate. Stick the scissor tip between the muscle and skin, pointing toward the skin and away from the muscle. Open the scissors to tear the skin from the muscle. You will see clear connective tissue. Pull the skin back gently. Use the scissors and forceps, to cut the skin and peel it away from the muscle below. Skin your chicken wing. Do NOT cut the muscles! They look like bundles of pale pink tissue. What happened to each muscle as you raised and lowered it?
Which bones in the arm moved? The biceps and the triceps are the muscles that work to lift and lower your arm. Your biceps are on the upper front portion of the arm, and your triceps are on the upper back portion, as shown below. Bicep Tricep Tendon The tendon is the white, tough, fibrous material that connects the muscle to the bone. The tendons connecting muscle and bone can be seen in several muscle groups. Where these tendons run over joints, like the elbow, they are often in well developed sheathes.
Such a sheath can be seen above. Do such sheathes exist in the Human elbow? You should be able to see the ligaments inside the joint. Observe and see how and where the ligaments and tendons attach. Scrape the cartilage and bone to see how different they are.
Look at the elbow joint. Identify at least one ligament. Ligaments connect bones together. Ligaments are around between the bones. At the surface of each bone forming the joint is a white, shiny, slippery substance called cartilage.
What is the purpose of cartilage in joints? Look at a the bones of the human arm. Identify the humerus, ulna and radius. Compare the similar features between the chicken wing and the human arm.
Both have a humerus, radius, and ulna. The main difference is that the phalanges that make up the fingers of people are fused in birds to allow for the attachment of feathers.
Conclusion Based on your observations, explain the roles of muscles, tendons, bones, and joints in the back- and-forth movement of the lower chicken wing. While fowls are not able to fly well, they still retain that ability to some extent. These modifications include:. The vertebral column has 39 separate bones and is divided into five sections or groups — the cervical vertebrae, the thoracic vertebrae, the lumbar vertebrae, the sacral vertebrae and the coccygeal vertebrae.
The vertebral column is often described by way of the vertebral formula that is:. The atlas-axis at the base of the skull is quite different to all other bones of the vertebral column. The atlas is small and ring-like with a deep cavity for articulation moving together with a single projection, or condyle a rounded projection found on many bones , at the base of the skull. The axis, or epistropheus, is also specialised. It is short and projects from the cranial end and passes through the ring-like atlas.
It possess a small process, the dens, which allows the axis to articulate with the occipital condyle. This joint allows the head to turn on the neck. The seven thoracic vertebrae carry the ribs and all except the last have large ventral processes for the attachment of muscles.
Fusion of the second to fifth vertebrae provides rigidity for the structural strength necessary for flight. It is very difficult to separate the seventh thoracic, lumber, sacral and first coccygeal vertebrae because they are so closely fused for strength. Consequently, the lumbar and sacral vertebrae are usually treated as one group.
The last of the coccygeal are fused to form the pygostyle and provides a strong foundation for the tail feathers. There are seven pairs of ribs originating on the thoracic vertebrae and all but the first, second and sometimes the seventh do not reach the sternum, which is their other attachment point.
The third to the sixth have two segments:. All except the first and last have uncinate meaning hooked or bent processes that project backward over the outer surface of the next rib and connect to it by a ligament, which adds strength to the thoracic cavity. The sternum or breastbone is a complex shape and has been described as a quadrilateral, curved plate with processes projecting from each angle and from the middle of the cranial and caudal border.
The caudal medial projection, or metasternum, is the longest projection and carries the tall plate like ridge or sternal crest that runs from front to back on its ventral surface. This crest is more commonly called the keel bone and provides a suitable attachment for the major muscles of flight — the pectoralis and subcontractors muscles. The distinction between the two is very easy because of the two large orbits or openings into which the eyes fit. Two very thin bones, the sphenoid and ethmoid bones, together form the very thin septum that separates these orbits.
The cranial external appearance suggests a larger brain capacity than there really is. This is because the bone is formed by two layers of dense bone separated by a layer of very spongy bone. The spongy bone contains pockets of air derived from the eustachian tubes that connect the upper respiratory system with the middle ear. Large hemispherical cavities at the rear called the tympanic cavities form the location for the eardrum.
Openings at the base of the cranium provide for the direct connection of the brain with the spinal cord, and common openings in each lateral part of the occipital bone provide for the carotid arteries and jugular veins. The two optic nerves enter the cranial cavity by one common opening. The hyoid bone is found beneath the skull and forms the framework for the tongue.
It has three major sections — the entoglossal, the basi-hyal and the third section is itself in three parts. The entoglossal is contained within the tongue and a movable joint connects it with the basi-hyal and hence the remainder of the bone. The skeleton of both the forelimb or wing and the leg is very similar to those of theropod dinosaurs. They are essentially pentadactyl five digits limbs modified for the special purpose of flight and specialised feeding.
The scapula is narrow, thin and slightly curved which is unlike the shoulder blade of other animals. At the cranial end a section of a cavity receives the head of the humerus. The coracoid is the strongest bone of the shoulder girdle. One end carries a flattened articular surface to fit into the sternum.
At this end is a hole, or foramen, for the connection of the clavicular air sac a pneumatic bone. The other end connects with the clavicle. The clavicle or collarbone is thin, rod-like and slightly bent.
Its upper, or dorsal, end is connected with the coracoid bone. The combined clavicles form a bone called the furcula that is capable of acting like a spring and provides a firm base of support for the wing.
An opening formed by the shape of the scapula, coracoid and clavicle where they join provides a passage for the tendon of the muscle supracoracoides for connection to the humerus. The humerus is a large long bone with an ovoid head for articulation with the scapula, coracoid and clavicle. It is a pneumatic bone with a connection with the clavicular air sac. The two bones of the forearm are the ulna the thicker and longer , and the radius that lies laterally to the ulna. The large space between the ulna and radius is called the interosseus space.
The manus, or hand, consists of the carpus, metacarpus and the digits. The carpus of an adult contains only two bones — the ulnar and radial note different spelling that represent the proximal row of mammalian carpal bones. In the embryo, cartilaginous nodules represent the distal row but these fuse with the metacarpus and disappear. In the adult, the metacarpus is in the form of a single bone that is produced by the union of three elements that correspond to the first, second and third metacarpal bones of the theropod limb.
Modification and fusion has reduced the number of recognisable digits to three which are carried by the metacarpals. Unlike with other animals, such as mammals, the bones of the opposing sides of the pelvis do not meet on a mid ventral line.
They are at their widest separation in this location. This difference could be seen as a weakness, however it is compensated for by the extensive fusion of the hipbone and the vertebral column. The hipbone, in fact, consists of three bones — the ileum, the ischium and the pubis which all meet at a deep concavity called the acetabulum, into which the head of the femur fits.
The ileum is fused to the last thoracic, lumbar and sacral vertebrae to provide strength and rigidity. Remember, before we made any cuts we moved this wing by pulling down on this muscle. But we could see that when we pull down on the bottom of this wing it made the wing stretch out completely. Grab this muscle and watch how when you pull down on it, it can make the wing stretch out completely.
You can imagine that this muscle and this tendon are working with the bones in the wing tip, and probably other muscles and tendons, to make it move. This answers our questions: what structures are under the skin and how do they work together to allow the wing to move like that? Nerves tell the wing what to do but the muscles and the tendons and the bones are all connected and moving to allow the entire wing to move like a chicken wing does.
Here you can use your scissors and your hands to do that. Notice your fingers can easily go in to this area of the muscle around the bone.
You will feel the bone. Go ahead and pull on the wing, on the bone. Not like it did when the tendons and the muscle and the bone were all attached together and moving.
What structures are under the skin and how do they work together to allow the wing to move like that? Soon you will be cleaning up, but before you throw the wing away, I want you to take one more look at the wing and talk with a partner about the structures that are a part of this wing.
Use the wing to point out the bone and the muscle and the tendon and the skin, because you will be recording all of these structures in your student science notebook.
Go ahead and turn and talk with a partner about the structures that you found in the wing. Remember how muscles and bone in the wing made the wing tip move and stretch out before we cut the tendon. I want you to turn and talk again to your partner about how these structures work together so that the animal could move. Go ahead and turn and talk to your partner.
Congratulations, you have successfully completed a dissection. Remember, you need to throw the plate and the gloves and the wing in the garbage and clean your area thoroughly and wash your hands with warm water and soap.
Keep in mind all that you have learned through the dissection because you will be recording the new learning in your student science notebook. You now know how structures work together underneath the skin of this wing and even our skin to allow us and this wing to move.
To access hundreds of premium or staff resources, log in or sign up for an account. Relive the learning from the Virtual Summit. Transcript - [Presenter] Hello, today you will be dissecting a chicken wing to understand how different structures, like muscles and nerves and bones work together to allow the chicken to move.
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