When a stem cell divides, each new cell can either stay a stem cell or become a specialized cell, such as a muscle cell, a red blood cell, or a brain cell.
Answer:
This is called wind shear, and it can induce a spinning movement in the air. At first this creates a spinning cylinder of air that is parallel to the surface. But as with any thunderstorm, the convective cells in a hurricane create strong updrafts. These can tilt the spinning air upright; a tornado is born.
Answer:
Oxygen and pyruvate.
Explanation:
The krebs cycle is a stage of cellular respiration and occurs in aerobic organisms. In this case, we can say that the Krebs Cycle only occurs in the presence of oxygen, being essential for the completion of cell respiration.
The Krebs cycle only occurs after the completion of glycolysis, as it needs to be initiated by pyruvate, which is a molecule resulting from glycolysis. In this case, in addition to oxygen, the presence of pyruvate is essential for the krebs cycle to occur.
1.) similar fossils were found on different continents.
2.)the continents seemed to fit together; they were like a spread apart puzzle.
3.)geographical features and mountain ranges lined up with the same rock composition
4.)glacier grooves in rocks led him to trace them out to where they started
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