The above diagram represents a longitudinal section of a root. A root is the part of the plant that typically lies below the surface of the soil and serves to anchor the plant in place and absorb water and nutrients from the soil. A longitudinal section is a cut that runs lengthwise through the root, dividing it into two halves. The diagram shows various parts of the root, including the root cap, which protects the tip of the root as it grows through the soil, the root hairs, which increase the surface area of the root for better absorption of water and nutrients, and the vascular cylinder, which contains the xylem and phloem that transport water, nutrients, and sugars throughout the plant.