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
The abdominal cavity does not have a bony protection. The abdominal cavity is barely an unfilled space. It comprises a quantity of critical body organs containing the subordinate portion of the esophagus, the stomach, the small intestine, the colon, the rectum, the liver, the gall bladder, pancreas, spleen, kidneys, and bladder.
Asexual reproduction involves one parent and produces offspring that are genetically identical to each other and to the parent. Sexual reproduction involves two parents and produces offspring that are genetically unique.
Answer:
A cell is a mass of cytoplasm that is bound externally by a cell membrane. Usually microscopic in size, cells are the smallest structural units of living matter and compose all living things. Now put that into your own words.
Explanation:
The endoplasmic reticulum is an organelle that is responsible for the synthesis of lipids and the modification of proteins.
