Answer:
Open channels allow an influx of sodium ions into the cytoplasm of the muscle fiber. The sodium influx also sends a message within the muscle fiber to trigger the release of stored calcium ions. The calcium ions diffuse into the muscle fiber.
Explanation:
Answer:
an organism with nutritional requirements
Explanation:
Every cell in the body goes through a life cycle. Cells grow and divide to replace cells that are lost because of normal wear and tear or injury. Different cells grow and die at different rates. Some cells, such as epithelial<span>epithelialA thin layer of epithelial cells that makes up the outer surfaces of the body (the skin) and lines hollow organs, glands and all passages of the respiratory, digestive, reproductive and urinary systems.</span> cells, reproduce quickly. Other cells, like nerve cells, grow slowly. Both normal cells and cancer cells go through a sequence of steps, or phases, when they form new cells. This is called the cell cycle.
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Explanation:
Platypus is well adapted for semi-aquatic lifestyle. Its streamline body and a broad, flat tail are covered with dense waterproof fur, which provides excellent thermal insulation. ... The Platypus uses its tail for storage of fat reserves and the strong claws on its feet for burrowing and moving on land.
