Bacillus anthracis, the bacterium that causes the deadly disease anthrax produces thick endospores. what is the significant role of spore formation in the reproductive cycle of this bacterium

Many bacteria are able to form a structure called an endospore which is  a thick covering made of protein. This is considered an extreme survival strategy that allows the cell to survive is the most unfavorable conditions. When the bacteria is not able to reproduce because the environment would not favor reproduction, the bacterium forms an endospore to lay dormant until conditions change. 

C. gemstones they are the only non metallic mineral from the list.

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