Mineral Nutrition & Transport in Plants MCQ MBBS CEE Entrance Nepal
Mineral Nutrition and Transport in Plants
Introduction
Mineral nutrition is essential for plant growth and development, providing the necessary nutrients for various physiological functions. Plants absorb minerals from the soil, which are crucial for processes such as photosynthesis, respiration, and enzyme activity.
Essential Nutrients
Plants require a range of mineral nutrients, which can be classified into macronutrients and micronutrients:
1. Macronutrients
These are needed in larger quantities and include:
- Nitrogen (N): Essential for amino acids, proteins, and nucleic acids.
- Phosphorus (P): Important for energy transfer (ATP) and DNA/RNA structure.
- Potassium (K): Regulates osmotic balance and enzyme activation.
- Calcium (Ca): Vital for cell wall structure and signaling.
- Magnesium (Mg): Central component of chlorophyll and enzyme cofactor.
- Sulfur (S): Integral for amino acids and vitamins.
2. Micronutrients
These are needed in smaller amounts but are equally important. They include:
- Iron (Fe): Necessary for chlorophyll synthesis and electron transport.
- Manganese (Mn): Involved in photosynthesis and enzyme activation.
- Zinc (Zn): Important for protein synthesis and growth regulation.
- Copper (Cu): Involved in photosynthesis and respiration.
- Boron (B): Essential for cell wall formation and reproductive development.
- Molybdenum (Mo): Important for nitrogen fixation and enzyme activity.
Mineral Transport in Plants
Minerals are transported within plants through two main pathways:
1. Xylem Transport
Minerals absorbed by roots are primarily transported through the xylem tissue, which also carries water. This movement occurs via transpiration pull, where water evaporates from leaves, creating negative pressure that draws water and dissolved minerals upward from the roots.
2. Phloem Transport
While phloem primarily transports organic nutrients (like sugars), it can also transport certain minerals. This occurs through a process known as translocation, where nutrients move from source (e.g., leaves) to sink (e.g., roots, fruits) tissues.
Conclusion
Understanding mineral nutrition and transport is crucial for optimizing plant growth and improving agricultural practices. Adequate mineral availability and effective transport mechanisms contribute to the overall health and productivity of plants.
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