Transport in Plants Flashcards
What are the two types of vascular tissues in plants?
Xylem and Phloem.
What is the function of the xylem?
It transports water and mineral ions from roots to leaves and provides structural support.
What is the function of the phloem?
It transports sucrose and amino acids from leaves to the rest of the plant (translocation).
How does water enter root hair cells?
By osmosis, from high water potential in the soil to lower water potential in the root.
How are mineral ions absorbed by root hair cells?
By active transport, using energy.
What are the adaptive features of root hair cells?
- Large surface area for faster absorption.
- Thin walls for a short diffusion distance.
- Large number of mitochondria to produce energy for active transport.
What is transpiration?
The evaporation of water from the spongy mesophyll cells and its diffusion out through the stomata.
Why is transpiration important?
- Cools down the plant.
- Creates a pulling force (suction) that helps transport water and minerals from root to leaf.
How does temperature affect transpiration?
Higher temperatures increase kinetic energy of particles, leading to faster evaporation and increased transpiration.
How does light intensity affect transpiration?
Higher light intensity keeps stomata open longer, allowing more water to escape, increasing transpiration.
How does wind affect transpiration?
Wind removes water particles near the stomata, maintaining a steep concentration gradient and increasing transpiration.
How does humidity affect transpiration?
High humidity reduces the concentration gradient, leading to lower transpiration rates.
What is a mass potometer used for?
To measure the mass decrease of water due to transpiration over time.
What is a bubble potometer used for and what unit is used to describe it?
To measure the distance an air bubble moves in a capillary tube over time, indicating the rate of water uptake (rate of transpiration).
What is the purpose of the reservoir in a bubble potometer?
It resets the bubble’s position for repeated measurements.
