The seed coat primarily serves as a protective layer surrounding the seed, ensuring its integrity during the development and dispersal stages. It shields the embryo from physical damage, pathogens, and environmental elements like extremes in temperature and moisture. This protection enables seeds to withstand unfavorable conditions until they find a suitable environment for germination. Additionally, the seed coat plays a part in the seed dormancy process, regulating when a seed may germinate based on external stimuli. By functioning as this barrier, the seed coat significantly impacts the reproductive success of plants.