The muscles in our body are only able to pull the atached bones, therefore they need an opposing force so that they can go back to their original position. All skeletal muscles have an opposing muscle or pair. When one of the muscles contracts, the opposing relaxes.
2. Identify the structures that make up a skeletal muscle.
- Muscle fiber: contains nuclei and is a long cylindrical muscle.
- Myofibrils: are found inside the muscle fibers
- Sarcomere: is the unit that contracts in the muscle and has two kinds of filaments: Thick=myosin and thin= actin.
- Myosin: composed of proteins and have bumplike projections.
- Actin: have a twisted structure and are composed of protein.
3. Identify at least three organ systems involved in a handshake. Describe what each system contributes to the handshake.
Eyes: the eyes can perceive the precense of the other person and send these images or messages to the brain.
Brain: is the control center of the body. The brain sends messages to the muscles through the nerves.
Muscles: The muscles of the back, shoulder, upper arm, forearm and wrist perform contractions and relaxations in order to give the handshake.
4. Explain how actin and myosin interact as a muscle cell contracts.
For each contraction, the myosin head bind to the actin or thin filament, then the myosin heads bend letting the actins move towards the center of the sarcomere. ATP binds to each myosin head and releases it from the actin.
I like how you answered each question because they are very complete. For example in number two you have all the parts and they look very organized
ReplyDeleteI trully thought that you made a great job waht I would have included will be that muscles can only pull and not push. Maybe in the second question I would have added how this skeletal muscles work, but overall your work was truely fantastic.
ReplyDeleteI liked the way you presented you information in a clear and easy way to understand. In the second question i would have included a little more information of wha the brains function is in the handshaking due to it being the one that controls a big majority of it.
ReplyDeleteYour answers were fully completed, no negative comments.
ReplyDeletei liked your answer for number 4 because it was not that long but it had all the necessary terms, in number 3 I think it was important to put the function of the nervous system.
ReplyDeleteYour answers to the questions were very complete and clear. However, in question number three you should have read better the question, It is asking for organ systems and not only for organs. I really liked how you answer the first question. It was really complete and very clear. Good work!
ReplyDeletei like your detail answers
ReplyDeleteKaro,
ReplyDeleteI love your detailed answers. They were extremely specific and provided great insight on what was taught on chapter 27.5.
The way you explained and outlayed question number one really cleared my doubts when doing my blog questions about myosin and actin and there relationship for muscle contraction.
Great work overall and practical layout! :)