Ohio Assessment for Educators (OAE) Integrated Science (024) Practice Exam

Where does the majority of water absorption occur in plants?

1. Stems

2. Leaves

3. Roots

4. Flowers

The correct answer is: Roots

The majority of water absorption in plants occurs in the roots. Roots are specifically designed for this function, featuring root hairs that significantly increase the surface area available for absorbing water and nutrients from the soil. The process of osmosis allows water to move from the soil into the root cells, which often have higher concentrations of solutes than the surrounding soil, facilitating the uptake of water. In addition to water absorption, roots are also critical for anchoring the plant and accessing nutrients. The structure of roots, including the presence of vascular tissues, enables the effective transport of absorbed water and nutrients to other parts of the plant, such as stems and leaves, where they are utilized in various physiological processes. While stems, leaves, and flowers play essential roles in a plant’s overall function, their primary functions do not focus significantly on water absorption. Stems mainly provide support and conduct water and nutrients, leaves are primarily responsible for photosynthesis, and flowers are related to reproduction. Thus, the role of roots in water absorption is far more specialized and crucial for plant health and vitality.