Summary
Transport in plants involves the movement of water, minerals, and nutrients through different plant structures. The epidermis is a single layer of cells on the outer side of the stem that protects the stem and reduces water loss. Example: It acts like a skin for the plant.
- Cortex — packed cells that fill the volume of the stem. Example: Acts as storage for nutrients.
- Vascular Bundle — bundle of transport vessels including phloem, cambium, and xylem. Example: Like a highway system for nutrients and water.
- Phloem — vessel that carries food and plant hormones. Example: Transports sucrose from leaves to roots.
- Cambium — layer that separates phloem and xylem and grows new cells. Example: Helps the plant grow thicker.
- Xylem — vessel that carries water and minerals. Example: Moves water from roots to leaves.
- Pith — packing cells at the center of the stem. Example: Provides structural support.
- Root Hairs — single-celled extensions that absorb water and minerals. Example: Increase surface area for absorption.
Exam Tips
Key Definitions to Remember
- Xylem: Transports water and minerals from roots to leaves.
- Phloem: Transports nutrients like sucrose and hormones throughout the plant.
- Transpiration: Loss of water vapor from leaves.
Common Confusions
- Xylem and phloem directions: Xylem only moves water upwards, while phloem can move nutrients in both directions.
- Transpiration vs. Translocation: Transpiration involves water movement, while translocation involves nutrient movement.
Typical Exam Questions
- What is the function of xylem? Transports water and minerals from roots to leaves.
- How does phloem transport differ from xylem? Phloem transports nutrients in both directions using energy.
- What role do root hairs play in plant transport? Increase surface area for water and mineral absorption.
What Examiners Usually Test
- Differences between xylem and phloem structures and functions.
- The process and importance of transpiration in plants.
- How root hairs facilitate water uptake.