The genetic material, DNA, must undergo replication before a cell enters mitosis. DNA replication results in two identical copies of the DNA.
The Precambrian time refers to the time 4.5 billion to 542 millions year ago. This period is characterized by having reduced atmosphere and included reduced compounds. Scientists believed that atmosphere at that time was devoid of free oxygen and CO2 was present in excess. Before the complex life evolved on the Earth, the Precambrian Earth's ocean contained dissolved carbon dioxide.
Which is the first indicator of an infection in the body?
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B. an increase in the number of WBCs in the blood</span>