Minerals

Explain why plants require minerals from the soil for healthy growth.
State the key roles of nitrates, phosphates, potassium, and magnesium.
Describe how plants absorb dissolved minerals from the soil through root hair cells and transport them upwards.
Describe the symptoms of deficiency for nitrates and magnesium and explain the purpose of using fertilisers.

Just like humans need vitamins, plants need certain minerals from the soil to grow properly and stay healthy.
Plants need several minerals, but four important ones are:
- Nitrates (containing Nitrogen): Crucial for making amino acids. Amino acids are the building blocks used to make proteins, which plants need for healthy growth, especially making new leaves and shoots.
- Phosphates (containing Phosphorus): Essential for healthy root growth.
- Potassium: Needed for producing healthy leaves and flowers.
- Magnesium: Required to make chlorophyll, the vital green pigment that absorbs sunlight for photosynthesis.

Minerals are found naturally in the soil.
They dissolve in the water present in the soil.
Plants absorb this mineral-rich water through their root hair cells.
These dissolved minerals then travel up the plant through the xylem tubes, along with the water.

If a plant doesn't get enough of a particular mineral, its growth will be poor, and it will show signs of mineral deficiency.
Different deficiencies cause different symptoms:
- Nitrate Deficiency: Results in poor overall growth, and the older leaves often turn yellow.
- Magnesium Deficiency: Causes yellowing of leaves (because the plant can't make enough green chlorophyll).
- Phosphorus Deficiency: Leads to poor root development, and younger leaves might develop a purplish tint.
- Potassium Deficiency: Can cause leaves to turn yellow, often with dead spots or patches appearing.

When crops are grown and harvested year after year, they continuously remove minerals from the soil.
Over time, the soil becomes depleted, and future crops may suffer from mineral deficiencies.
Fertilisers are chemicals added to the soil by farmers and gardeners to replace these essential minerals.
Many common fertilisers are labelled 'NPK' because they contain the three main minerals needed in large amounts: Nitrogen (from nitrates), Phosphorus (from phosphates), and K (the chemical symbol for Potassium).

Minerals: Essential chemical elements absorbed by plants from the soil, needed for healthy growth and development.
Nitrates (containing Nitrogen): Minerals needed by plants to make amino acids and proteins for growth.
Phosphates (containing Phosphorus): Minerals important for healthy root growth.
Potassium: A mineral needed for healthy leaves and flowers.
Magnesium: A mineral required by plants to make chlorophyll.
Root hair cells: Extensions of root cells that increase the surface area for absorbing water and dissolved minerals from the soil.
Mineral deficiency: A condition where a plant lacks sufficient amounts of a particular essential mineral, leading to poor growth and specific symptoms.
Fertilisers: Substances added to the soil to provide plants with essential minerals that may be lacking.
NPK: A common abbreviation on fertilisers indicating the presence of Nitrogen (from nitrates), Phosphorus (from phosphates), and Potassium.

Design and conduct a simple experiment to demonstrate mineral deficiency symptoms in plants by growing them in solutions lacking specific minerals (e.g., comparing growth in a complete nutrient solution vs. one without nitrates).
Research the environmental impacts that can be caused by the overuse or runoff of fertilisers from fields into nearby water bodies, such as eutrophication.