Photosynthesis, for example, is a way that plants take energy from the abiotic environment and incorporate it into the biotic environment by synthesizing sugars and proteins from it. Other components of the biotic environment, such as herbivores, eat the plants and transfer the nutrients further along the chain.
Source: Adaptec. Backplanes are the fundamental building block to any storage appliance that is meant to support hot plugging. So, SAS expanders will always go hand in hand with powerful backplanes (whether these are in a single box or not).
SATA RAID Backplane Cages A RAID cage is an internal multi-bay backplane module designed to hold hard drives in a removable configuration. Hot-swap RAID operation requires a RAID controller card.