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Iron is a chemical element with symbol Fe and atomic number 26. It is a metal in the first transition series. It is by mass the most common element on Earth, forming much of Earth's outer and inner core
The cells that produce pepsin, an enzyme that breaks down proteins during the digestive process is Chief cells. Pepsin is the main digestive enzyme in the stomach that breaks down proteins. Pepsin is produced by the chief cells in the inactive form pepsinogen, which is then converted to pepsin by the hydrochloric acid from the parietal cells.
Easy answer: its too hot.
The deepest man made hole is Kola Superdeep Borehole. That was a Russian experiment to see how deep you could drill into earths crust, reaching down 12,262 meters. At that depth the temperature reached 180 °C. The scientists estimated that a 15,000 meters depth the temperature would reach 300 °C, and at that temperature the drill would cease to work and the project was stopped.
