<span>There are numerous proteins in muscle. The main two are thin actin filaments and thick myosin filaments. Thin filaments form a scaffold that thick filaments crawl up. There are many regulatory proteins such as troponin I, troponin C, and tropomyosin. There are also proteins that stabilize the cells and anchor the filaments to other cellular structures. A prime example of this is dystrophin. This protein is thought to stabilize the cell membrane during contraction and prevent it from breaking. Those who lack completely lack dystrophin have a disorder known as Duchene muscular dystrophy. This disease is characterized by muscle wasting begininng in at a young age and usually results in death by the mid 20s. The sarcomere is the repeating unit of skeletal muscle.
Muscle cells contract by interactions of myosin heads on thick filament with actin monomers on thin filament. The myosin heads bind tightly to actin monomers until ATP binds to the myosin. This causes the release of the myosin head, which subsequently swings foward and associates with an actin monomer further up the thin filament. Hydrolysis and of ATP and the release of ADP and a phosphate allows the mysosin head to pull the thick filament up the thin filament. There are roughly 500 myosin heads on each thick filament and when they repeatedly move up the thin filament, the muscle contracts. There are many regulatory proteins of this contraction. For example, troponin I, troponin C, and tropomyosin form a regulatory switch that blocks myosin heads from binding to actin monomers until a nerve impulse stimulates an influx of calcium. This causes the switch to allow the myosin to bind to the actin and allows the muscle to contract. </span><span>
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Answer:
The correct option is: 4. Heat at 62.8 degrees C for 30 minutes
Explanation:
Pasteurization is the process or technique of heating packaged as well as the unpackaged liquid food, to remove pathogens and extend the shelf life. In this process,<u> the food is usually heated at temperatures below 100 °C.</u>
Originally, this process involved heating the food at 72.2 °C for 15 seconds and <u>62.8 °C (145 °F) for 30 minutes, for batch pasteurization.</u>
James B. Connolly of Massachusetts was the first modern Olympic champion to be rewarded with a silver medal. He represented the Suffolk Athletic Club
Horses sleep while standing, unless it is necessary for them to get REM sleep. The amount of REM sleep needed is not much, so they will spend most of their time when sleeping, standing.
Explanation:
2) E) ribosome .
3) c) cytoskeleton: The cytoskeleton is a series of fibers made from proteins. It provides structure to the cell and gives it its shape it its shape.
4) a) chloroplast
