Plant Biology looks at botany: the structure and function of plants.
Water in Plants
Water enters plants in the roots, travels to the xylem by the symplast or apoplast pathway. It moves up the xylem by cohesion-tension because of the polar nature of water. Xerophytes are adapted to dry conditions. See Water in Plants
Transpiration is the movement of molecules through the plant, to the leaf where water vapour leaves via the stomata. The leaf has a waxy cuticle and guard cells to control the rate of transpiration. See Transpiration
Roots and Translocation
The root has an epidermis, endodermis and parenchyma - phloem and xylem vessels run through the middle. Translocation is the mass flow of sugar through the plant. Evidence is in ringing and radioactive experiments. See Roots and Translocation
Auxins are plant growth hormones, they make cells grow longer and divide. A growth reaction is called a tropism (phototropism, hydrotropism). Plant hormones also have commercial applications in cuttings and weed killing. See Plant Growth
The simple plant cell has a cell wall, vacuole and chloroplasts, which animal cells don't. Plant cells can be adaptated, for instance, palisade leaf cells have lots of chloroplasts and are on the top surface of leaves. See Plant Cells