OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

What are root hair cells specialized for?

1. Photosynthesis in roots

2. Active transport of nitrates from the soil

3. Providing structural support to plants

4. Transporting water to the leaves

The correct answer is: Active transport of nitrates from the soil

Root hair cells are specialized for the active transport of nitrates and other minerals from the soil into the plant. These cells are located at the tips of roots and have long, hair-like projections that increase the surface area for absorption. This adaptation allows for enhanced uptake of essential nutrients, including nitrates, which are vital for plant growth and development, particularly for the synthesis of amino acids and proteins. The structure of root hair cells includes a large vacuole and a permeable cell membrane that facilitates the transport of ions and nutrients. The use of active transport is important because it allows the plant to absorb nutrients even when their concentration in the soil is lower than that within the cell, ensuring that the plant can effectively gather the resources it needs for healthy growth. Other options, such as photosynthesis in roots, structural support, and transporting water to the leaves, do not accurately describe the primary role of root hair cells, which is centered around nutrient absorption.