Unit 7 Reflection

chicken lab
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Reflection
From the very beginning of this unit, we were tested in our vocabulary regarding the different movements of the synovial joints and muscles. These key actions were actually very helpful as we went through the rest of the unit, and it served as a sturdy foundation for us to learn about how these movements were made possible. Simple ones like rotation and elevation/depression seemed easy to understand, but supination/pronation and plantar flexion/dorsiflexion were harder to pick up. All the movements, however, really showed us how many different types of movements different body parts made, as they couldn't be all the same, or that would make life a lot harder for us. The contraction and stretching of a muscle really got to me the most as we learned about just how each muscle contracted. There are so many smaller elements like the fibers and the actin and the myosin that really make the process a little bit more complicated than step 1: contract the muscle. There's chemical processes with Ca2+ and ATP and there's also physical processes like the power moves and all of them work together to do one task. Additionally, in our extremely hands on chicken dissection lab, although we only looked through some uncooked food, in reality we actually discovered a lot of names of the different muscles within the bodies of a chicken. While not all of them were sized and shaped like the ones in our bodies, there were similarities between limb muscles that really helped us realize the real life application and learning about the muscles in our own bodies. Learning location and function of each muscle really broadened our horizon on just "muscle." Also learning about the conditioning and steroid abuse helped us gain some world view on how things are happening now, and also how we should take care of our own muscles and our body health to avoid health hazards. There was just so much to absorb, and I know I learned all of the material when I was reading, listening, and noting. I just hope I still remember all of the information by the end of it. Times are surprisingly tough as a second semester senior, and I think there's still a lot of pressure that I really wish wasn't there. I still have the drive and the push to excel in academics, but there are a lot of challenging obstacles in the way. No matter what though, I'm powering through. That's how I've always done it and I'm getting through this dip and moving on.

Performance Enhancements Advertisement

Reflection

I've definitely heard of steroids before, but I had no idea how bad the side effects were. I thought they only had long term negative effects on the muscles, but there were a couple defects I didn't know about, like the reduction of sperm, or even something close to gender swapping, with the women's voice dropping and men developing breasts. It all makes sense, but it still is jaw dropping. I think most of the man made techniques and products are quite hazardous, but there are a few that I would regard as safer. Massages seem to only be positive, and while caffeine definitely can cause insomnia and even addiction, I can't tell you how many times I needed that extra boost to get me through school. Also, the diets were quite interesting, with the carbs and the proteins. I was doing some web surfing, and actually actors like Chris Evans, Hugh Jackman, and Chris Pratt often had to turn to certain protein diets and daily workout sessions to reach a certain physique for the role they were to cast. Most of their days consisted of lifting and eating pounds of chicken and fish, and simple greens like broccoli, but avoiding sugar and alcohol. It's definitely uncomfortable from what I've read, but that's probably because humans weren't exactly made to just be work out machines. It's fascinating that we can learn so much about these things which have so much real life application.

Chicken Dissection Lab

For this lab, we used a chicken carcass and dissected it to identify different muscles within the body. The objective was to learn more about the different types of muscles in the body, identify it by its shape and its look, and compare it to our own human muscles, which to a certain degree have similar aspects. By cutting through the skin and the connective tissue, we were able to see what the muscle really looked like and how it interacted with bones and tendons to manifest certain movements and actions. Initially going down the middle to see the pectoralis major and minor and flipping it over to locate the trapezius and latissimus dorsi, we then moved in on the wings, discovering muscles like the biceps brachii, the triceps humeralis, and the brachioradialis, which all have names that resemble muscles in our own arms. We got to see an excellent example of the tendon, not necessarily at work, but definitely how it functions. Tendons connect muscle and bone for movement, and the tendons at the biceps brachii kept the limb stabilized so when we bent the wings, the contraction was smooth and without disruption. Tendons at the origin would stabilize the muscle, and tendons at the insertion allowed the muscle to contract and move. We only got a good look at the tendons at the origin, but I'm sure the tendon at the insertion was there somewhere. To compare this chicken and our own anatomy, there were certainly several muscles and other things that were notable, especially in the limbs. We both have the humerus, the ulna, and the radius, but not only do we share the relatively same bone, we also share the same muscles attached to them like the biceps and the triceps. The proportions are different however, not only because of size, but because of the specific way they're positioned to advocate movement of the limbs. We don't flap wings because we have arms, and our fingers are much more delicate and more intricate in terms of movement. They are birds, and we are mammals, so that line still remains to differentiate us. 

The Sartorius is the the front of the thigh, allows for flexing

The Latissimus Dorsi extends the wings

The Trapezius is perpendicular to the spine and the shoulders

The Iliotibialis assists the Sartorius in flexing legs and also extends thighs

The Deltoid is a muscle that can be triggered to raise or life wings

Biceps Brachii flexes wings

Quads or Quadriceps, a group of four muscles, helps extend the lower leg

Gastrocnemius is the primary muscle of the medial and dorsal sides of the drumstick

The Brachioradialis is the largest muscle on the superior side of the lower wings

The pectoralis can pull both wings ventrally

The Latissimus Dorsi extends wings

The Peronus Longus is the primary superficial muscle on the lateral side of the drumstick.

Triceps humeralis extends and straightens wings

Peronus Longus

Flexor Carpi Ulnaris flexes the "fingers" and runs from back to elbow from the side of the wing

Pectoralis minor pulls the shoulders down and forward

Tibialis Anterior flexes the foot

What happens when you stretch?

"Just as the total strength of a contracting muscle is a result of the number of fibers contracting, the total length of a stretched muscle is a result of the number of fibers stretched -- the more fibers stretched, the more length developed by the muscle for a given stretch."

This quote summarizes well the limits of the "stretchability" of our muscles. Our bodies are only as capable as the structures within it, so naturally our functions match the number of fibers which are the elements that elongate during the process of stretching a muscle.

"Proprioceptors (also called mechanoreceptors) are the source of all proprioception: the perception of one's own body position and movement."

Alas, a new word. Proprioceptors are also called mechanoreceptors because I believe mechano- refers to the mechanical movement of machines, which our bodies are capable of. Machines aren't necessarily robots or electronic devices. It's actually a simple term in physics that means something that is capable of work. Therefore, our body is a machine, as it can use energy to work!

"When an agonist contracts, in order to cause the desired motion, it usually forces the antagonists to relax."

We learned about the prime mover and the antagonist in a recent lecture, and this goes in further to explain why exactly they are opposites. Not only do they counteract each other in contracting of a muscle, but in stretching as well, they also do opposite actions to stabilize the body while maintaining the action of work and stretching. 

Relate and Review
I'm pretty sure most of us knew that muscles contracted and stretched, because we either learned about it a long time ago, or we just realized it naturally in our daily movements. It's really fascinating to actually find out why and how it works, and it's also really cool to know that it's not exactly a simple task. While picking up a pencil may seem like a difficult task, there's the neurons that deliver the message to move, there's the fibers in our muscles to contract and relax accordingly so we can bend down and wrap our fingers around the object of desire. I can't wait to find out more, because at this point I don't know much, and there's definitely a lot more to the muscular system than contracting and stretching. It's also super fun to be able to know a little bit of physics along the way!