Chicken Muscle Dissection

In the Chicken Dissection Lab, we took the skin off the whole chicken and cut along the chicken's breast. There we identified the pectoralis major which humans use in the bench press. We also identified the pectoralis minor which lays directly beneath the pectoralis major.
Afterward, we identified the trapezius and latissimus dorsi which is located in the chicken's upper back. The trapezius runs perpendicular from the backbone to the shoulder but are split into two in humans. The part running up the neck help shrugs the shoulder while the part along the back pulls the shoulders back. The Lattisimus Dorsi help extends the arm and runs from the spine into the armpit.


Then, we removed one of the chicken's wing from the body. We located the deltoid which is the muscle on top of the shoulder for both birds and humans. The biceps brachii and triceps humeralis were pretty easy to identify as it is rather similar to muscles on a human.  We then extended the wing where we identified the flexor carpi ulnaris and brachioradialis.














Next, we removed the thigh from the rest of the chicken and found the sartorius, iliotibialis, biceps femoris, semimembranosus, semitendinosus, and quadriceps femoris.
Then, we looked at the drumstick where we identified the gastrocnemius, peroneus longus and tibialis anterior.

Pectoralis major: breast muscles of the bird, pull the wing ventrally which powers flight
Pectoralis minor: lifts the wings dorsally, which is the recovery stroke of the wing in flight, in humans this pulls the shoulder down & forward.
Trapezius: these muscles run perpendicular from the backbone to the shoulder of the bird and help pull the shoulder back
Latissimus dorsi: these muscles run from the spine into the wing or arm pit and attach to the posterior side of the humerus, extend/ pull the wing/ arm
Deltoid: raises the upper arm/wing
Biceps brachii: flexes the wing/arm, muscle on cranial side of upper wing/ arm 
Triceps humeralis: straightens the wing or arm, on inferior side of upper wing/ arm 
Flexor carpi ulnaris: largest muscle on posterior side of lower wing that flexes the hand
Brachioradialls: largest muscle on superior side of lower wing that pulls the hand back
Sartorius: muscles run down the front edge of the thigh from the ilium to the knee, flexes thigh & allows legs crossing 
Iliotibialis: covers the lateral side of the thigh in birds and extends the thigh and flexes the leg
Biceps femoris: makes up hamstring group, flexes leg 
Semimembranosus: inferior and medial to biceps femoris and extends the thigh
Semitendinosus: anterior and medial to semimembranosus on the inside of the thigh and extends the thigh
Quadriceps femoris: flexes the thigh and extends the lower leg
Gastrocnemius: primary muscle of dorsal and medial sides of the drumstick, helps extend the foot & flexes the lower leg 
Peroneus longus: primary superficial muscle on the lateral side of drumstick, extends the foot
Tibialis anterior: flexes the foot

Muscles are the ones doing the actual work when our body is in motion. They surround the bone which helps give us support and gives our body shape. Tendons are what attach muscle to bone. For example, the bicep and tricep are attached to the humerus and when the bicep contracts, the tendons help pull on the bone which causes the muscle to contract and shorten. The tendon of insertion moves when the muscle moves while the tendon of the origin side makes sure that the muscle stays attached to the bone during movement.