Girdling experiments, where the bark of a tree is removed in a ring around the trunk, demonstrate the importance of phloem for translocation. Which observation is NOT expected after girdling?
Accumulation of sugars above the girdle.
Swelling of the bark above the girdle.
Eventual death of the roots due to lack of nutrients.
Increased sugar concentration above the girdle and decreased sugar concentration below the girdle, with no effect on xylem function.
Related Questions
Which of the following is NOT a characteristic of the apoplastic pathway?
Movement through cell walls
Movement through intercellular spaces
Unregulated movement until the Casparian strip
Movement through plasmodesmata
Transpiration contributes to the cooling of leaf surfaces. This cooling effect can be as much as:
2°C
10°C
20°C
30°C
Which of the following is NOT a long-distance transport pathway in plants?
Xylem
Phloem
Apoplast
Symplast
A researcher is studying long-distance transport in a plant. They introduce a radioactive tracer into the phloem sap of a source leaf. Which of the following would LEAST likely be observed after a period of time?
Movement of the tracer towards a developing fruit
Presence of the tracer in the root tips
Detection of the tracer in a sink leaf
Significant accumulation of the tracer in mature xylem vessels of the source leaf
Which of the following correctly describes the apoplastic pathway in plants?
Movement through the cytoplasm
Movement through plasmodesmata
Movement through cell walls and intercellular spaces
Movement across cell membranes
If transpiration in a plant is significantly reduced, which of the following is MOST likely to occur?
Increased water uptake by roots
Decreased leaf temperature
Increased transport of minerals
Increased leaf temperature
The cohesion-tension theory explains the ascent of sap in the xylem primarily due to:
Root pressure
Capillary action
Active transport of water
The cohesive properties of water and transpiration pull
The upward movement of water in tall trees is primarily driven by:
Root pressure
Capillary action
Transpiration pull
Active transport
The movement of minerals through the apoplast is interrupted at the:
Epidermis
Cortex
Casparian strip
Phloem
The Casparian strip in the endodermis primarily restricts the movement of water via the:
Apoplast
Symplast
Transmembrane pathway
Vacuolar pathway
