Plant adaptations to life on land include the development of many structures — a water-repellent cuticle, stomata to regulate water evaporation, specialized cells to provide rigid support against gravity, specialized structures to collect sunlight, alternation of haploid and diploid generations, sexual organs. There are four major challenges to plants living on land: obtaining resources, staying upright, maintaining moisture, and reproducing. Obtaining Resources From Two Places at Once Algae and other aquatic organisms acquire the resources they need from the surrounding water