Uptake and Transport of Mineral Nutrients
Explains the mechanisms of mineral ion uptake (active and passive absorption) and their translocation within the plant body.
What is Uptake and Transport of Mineral Nutrients?
Movement of ions across a membrane without the expenditure of metabolic energy, typically down a concentration gradient.
Key points
- Differentiate between passive and active absorption of mineral ions.
- Explain the role of root structure in mineral uptake.
- Describe the pathway of mineral transport from soil to xylem.
- Understand the mechanism of translocation of minerals in the plant.
Common exam trap
Confusing passive and active transport mechanisms.
Definitions
- Term
Passive Absorption
- Meaning
Movement of ions across a membrane without the expenditure of metabolic energy, typically down a concentration gradient.
- Term
Active Absorption
- Meaning
Movement of ions across a membrane against a concentration gradient, requiring metabolic energy (ATP) and specific carrier proteins.
- Term
Casparian Strip
- Meaning
A band of suberin in the radial and transverse walls of endodermal cells, preventing apoplastic movement of water and solutes into the stele.
- Term
Transpiration Stream
- Meaning
The continuous movement of water and dissolved minerals from the soil, through the plant, and into the atmosphere via transpiration.
Learning objectives
Differentiate between passive and active absorption of mineral ions.
Explain the role of root structure in mineral uptake.
Describe the pathway of mineral transport from soil to xylem.
Understand the mechanism of translocation of minerals in the plant.
Prerequisites
Cell Structure and Function
Plant Anatomy (Root structure)
Water Potential
Transport Across Membranes (Diffusion, Osmosis, Active Transport)
Common mistakes
Confusing passive and active transport mechanisms.
Underestimating the role of ATP in active uptake.
Forgetting the selective barrier function of the endodermis.
Attributing mineral transport solely to diffusion without considering the transpiration stream.
Keywords
Mineral Uptake
Active Transport
Passive Transport
Root Absorption
Xylem Transport
Casparian Strip
Transpiration Stream
Ion Channels
Carrier Proteins
Practice preview
Which of the following statements is INCORRECT regarding the uptake of mineral nutrients by plants?…
easy
The movement of mineral ions into the root cells against their concentration gradient is known as:…
easy
Which of the following factors does NOT directly influence the rate of mineral absorption by plant roots?…
medium