The original DNA strands are used as a template during replication<span />
The burial practices of humans have not led to any significant changes in Earth's biome. Matter can not be created nor destroyed. Burial practices lead to burying the dead bodies into the Earth, where they are decayed by the action of several microbes and insects. The organic and inorganic compounds are added to the Earth.
Cells need to reproduce for growth, repair, or replacements. Cells divide whenever a tissue / organ / organism is growing or needs repair.
Hope this helps :)
It helps improve spike stability by alternating between crops with deep roots and those with shallow roots. Pests are also put off because their food source keeps changing.
Genetic variety i believe.