Question

What do organisms generally use for chemical reaction as a source from outside the body?​

Answer 1

Answer:

Since life on earth depends on carbon- based molecules, most of these food sources are also carbon-based. ... Oxidising-reducing reactions are some of the most common chemical means to break-down molecules. For this, many organisms use oxygen sourced from outside the body.

Answer 2

$\large{\frak{\red{Answer}}}$

${\mapsto}$Since life on earth depends on carbon- based molecules, most of these food sources are also carbon-based. ... Oxidising-reducing reactions are some of the most common chemical means to break-down molecules. For this, many organisms use oxygen sourced from outside the body.