Chicken Dissection Analysis

     This week we dissected a chicken! I have a much better understanding of the muscles now; it was really helpful to see the muscles attached to the bones and the tendons in front of me instead of on a paper. Signals from our brain are sent to muscles so that we can move. Tendons connect the muscles to the bone and help the muscles pull on the bones. While stretching, muscles move the bones by working together. For example, we are able to bend our elbow because the biceps and the triceps work together. When you bend your elbow, the bicep muscle contracts and the triceps muscle is stretched out. A big difference in the tendon of the insertion and the tendon of the origin is where they are located. Insertion is the movable end of the muscle, while origin is the immovable end of the muscle. The tendon of the insertion has to be more flexible than the tendon at the origin.
      Chicken muscles are pretty similar to human muscles function wise. For example, the wing muscles of the chicken was similar to the muscles in a human arm. In both the chicken and human, the biceps brachii flexes the elbow joint. The deltoid of the chicken also looked similar to a human deltoid in size and shape. There were also muscles that were very different in shape, like the trapezius. The chicken's trapezius ran from the backbone to the shoulder of the bird. In a human, the trapezius is split into two parts: one up the neck and one along the back. The whole front part the chicken was the pectoralis major. There was no rectus abdominus or external obliques in the chicken as there are in humans.

Here are the pictures we took!

The sartorius is the longest muscle in the body. It is responsible for lateral hip rotation and flexion of the thigh and knee,

The triceps humeralis extends the wing (birds) or arm. 

The trapezius extends the head. It also elevates and depresses the scapula.

The pectoralis minor pulls the shoulder down and forward.

The deltoid is responsible for the abduction, flexion, and extension of the arm.

The biceps femoris is part of the hamstring group. It flexes the lower leg.

The biceps brachii flexes the elbow joint. 

The iliotibialis extends the thigh and flexes the leg.

The latissimus dorsi extends, adducts, and rotates the arm medially.

The semitendinosus is anterior and medial to the inner thigh. It works with the semimembranosus to extend the thigh.

The gastrocnemius is the primary muscle of the posterior and medial sides of the drumstick.

The brachioradialis flexes the forearm at the elbow. It is responsible for pronation and supination.

The pectoralis major pull the wings of a bird ventrally so they can fly. In a human, the muscle flexes, adducts, and rotates the arm.

The peroneus longus is responsible for the extension of the foot. 

The flexor carpi ulnaris is responsible for the flexion of the hand.

The tibialis anterior runs along the lateral side of the shin bone and flexes the foot. 

We found tendons!