For each skeletal muscle that is contracting, there is an opposing muscle—one that is relaxed but that can contract and pull the bone back in the opposite direction.
2. Identify the structures that make up a skeletal muscle. Include these terms: muscle fiber, fascicle, myofibrils, actin, myosin, sarcomere.
2. Identify the structures that make up a skeletal muscle. Include these terms: muscle fiber, fascicle, myofibrils, actin, myosin, sarcomere.
consists of bundles of parallel muscle fibers along with a supply of nerves and blood vessels. Inside a muscle fiber are bundles of smaller units called myofibrils. A single myofibril consists of repeating units called sarcomeres. Each sarcomere is composed of two kinds of filaments, thin and thick. The thin filaments are composed of the protein actin and have a twisted, ropelike structure. The thick filaments are composed of the protein myosin and have bumplike projections called myosin heads.
3. Identify at least 3 organ systems involved in a handshake. Describe WHAT each system contributes to the handshake.
3. Identify at least 3 organ systems involved in a handshake. Describe WHAT each system contributes to the handshake.
Involves the cooperation of many of your body's organs, tissues, and cells.
4. Explain how actin and myosin interact as a muscle cell contracts.
In each mini-contraction (shown in Figure 27-18), myosin heads first bind to thin filaments. Next, the myosin heads bend, pulling the thin filaments toward the center of the sarcomere.
Answers are complete but not in your own words.
ReplyDeleteFor question 3, you should include the three systems and how they contribute, instead of making a general statement.