<span>The systemic study of natural world is called natural science. It is
concerned with the understanding of natural phenomena based on collected data,
knowledge or sense of experience by means of observation and experimentation. Natural
science is subdivided into two main branches: one is biological science or life
science which aims to study life and living organisms their function,
structure, evolution, growth, distribution and taxonomy second is physical
science which is also broken down into different branches, including Earth
science, astronomy, chemistry and physics.
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If a checkpoint fails or if a cell suffers physical damage to chromosomes during cell division, or if it suffers a debilitating somatic mutation in a prior S phase, it may selfdestruct in response to a consequent biochemical anomaly.
