Final answer:
Land plants have evolved protective structures and reproductive mechanisms that allow them to thrive in arid conditions by managing to maintain structure, protect gametes, and disperse seeds in the absence of constant water availability.
Step-by-step explanation:
Desiccation-resistant pores, protective and complex reproductive organs, and embryos enwrapped by parental tissues are critical adaptations that enable land plants to survive in arid conditions. These adaptations counteract the challenges posed by a terrestrial environment, which lacks the buoyancy and constant water supply of aquatic habitats. Plants have evolved features such as waxy cuticles, structural support to withstand gravity, mechanisms to protect from mutagenic radiation, and strategies for dry gamete dispersal. Furthermore, seeds with multiple layers of hardened tissue guard against drying out and allow plants to endure through periods when environmental conditions are less than ideal. Seed plants have successfully colonized various habitats due, in part, to the evolutionary developments of seeds and pollen, which are adapted for a dry land existence. Seeds possess a protective coat and storage tissue that supports the embryo's growth during dormancy and until favorable growth conditions present themselves. This enables plants not only to thrive in dry environments but also to spread geographically, avoiding competition with the parent plant.