Root hair cells take up water and mineral ions from the soil.
Root hair cells have a long, thin extension that grows out into the soil.
Explain how this helps the root hair cell to take up water.
Water enters root hair cells by osmosis. Mineral ions enter root hair cells by active transport.
Explain why mineral ions cannot enter root hair cells by diffusion.
Root hair cells contain many mitochondria.
Suggest why.
A gardener adds a large amount of fertiliser to the soil around some plants. The fertiliser dissolves in the soil water.
The plants start to wilt.
Suggest why.
114 exam-style questions on OCR GCSE Biology 2.2 The challenges of size, covering 2.2.1 Exchange surfaces and surface area : volume ratio, 2.2.2 Substances transported in organisms, 2.2.3 The human circulatory system, 2.2.4 The heart and blood vessels, 2.2.5 Red blood cells and plasma, 2.2.6 Uptake of water and mineral ions by plants, 2.2.7 Transpiration and translocation, 2.2.8 Xylem and phloem, 2.2.9 Environmental factors and water uptake, and 2.2.10 Using a potometer. Each one has a worked solution and a mark scheme showing where the marks go.