Answer:
According to the sliding-filament model of contraction, the muscle contraction occur due to the myosin heads propel the actin myofilaments toward the center of the sarcomere. This pulls the Z disks closer together, shortening sarcomere and the entire muscle
Explanation:
In the muscle fiber there are two proteins that facilitate the process of contraction, myosin and actin. Myosin is thicker and more abundant than actin, and its interaction is responsible for the process of muscle contraction.
Both molecules, myosin and actin, form bonds -called cross bridges- where the myosin heads produce the mobilization of actin towards the center of the sarcomere. Z discs are associated with actin myofibrils, so they come close, and promote the shortening of the sarcomere.
This process requires the action of calcium ions, which depolarize the muscle cell and consume energy in the form of ATP.
It should be noted that the myosin and actin molecules do not change their length, but their action causes the muscle fibers to shorten during contraction.
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Types of muscle contraction brainly.com/question/7117064
Answer:
diagram is weird and unrealistic but B is the only reasonable answer.
Explanation:
B only makes sense - everything else is unreasonable. Proteins don't become enzymes since enzymes are already proteins, there are no proteins, carbohydrates, or glucose molecules in the image.
When the Civil War ended, the big question concerned the state of the freed slaves of the South. Recovery of the southern economy depended on getting the freedmen back into the cotton fields. During the period of Reconstruction the Radical Republicans in Congress tried to convert the freedmen into small free-holding farmers, but the former slaves were simply not ready to manage their own farms. What emerged out of necessity was southern farm tenancy, a system of near slavery without legal sanctions.
The currently accepted value for the half-life of 14C is 5,730 years. This means that after 5,730 years, only half of the initial 14C will remain; a quarter will remain after 11,460 years; an eighth after 17,190 years; and so on.
