GACE Middle Grades Science Practice Exam

The protective covering that surrounds seeds in plants is known as the seed coat. This outer layer serves several important functions: it protects the developing embryo from physical damage and desiccation, and it can help prevent the entry of pathogens. The seed coat is typically tough and hard, providing a barrier that is essential for seed longevity and ensuring that the seed remains viable until conditions are favorable for germination.

In contrast, cotyledons are the first leaves that appear from a germinating seed and play a role in providing nourishment to the seedling until it can produce its own food through photosynthesis. The endosperm is the tissue within the seed that provides essential nutrients to the developing embryo. Transpiration refers to the process by which water evaporates from plant leaves and is not related to seed structure. Understanding the specific roles and characteristics of each part helps clarify why the seed coat is the correct answer for the protective covering of seeds.