The ports on your router are already switch ports. If they weren't, they'd have IP addresses associated with them. DHCP has nothing to do with routers or router functionality, it is included as an added feature. You can turn it off and the device is still a router.
The plant root system constitutes the major part of the plant body, both in terms of function and bulk. In terrestrial plants, the root system is the subterranean or underground part of the plant body while the shoot is the aboveground part. Roots are branching organs which grow downward into the soil, a manifestation of geotropism. Branching occurs irregularly and not from nodes as in stems.
Simply put, the root zone of plants is the area of soil and oxygen surrounding the roots of a plant. Roots are the starting point of a plants vascular system. Water and nutrients are pulled up from the oxygenated soil around the roots, called the root zone, and pumped in to all the aerial parts of the plant.