Upward Movement
Flow of Phloem Sap
Water Flow
From Source to Sink
100
Define cohesion.
The tendency of the same molecules to attract to one another.
100
The phloem sap flows through chains of cells called what?
Sieve-tube members
100
This structure regulates water and gas movement
What is the leaf stomata?
100
Phloem
What move sugars from where they are made to where they are used?
200
What are the two types of xylem "straws"?
Tracheids and vessel elements
200
What loses their ability to perform some of the necessary cellular functions?
Sieve tubes
200
This cell regulates the opening and closing of the leaf stomata
What are guard cells?
200
Sugar Sink
Where is sugar is stored or used
300
Explain transpiration.
The loss of water through leaves due to evaporation generating the upward pull of water.
300
Does the phloem's sieve-tube members die or remain alive?
They remain alive, but lose their nuclei and some other organelles
300
This process allows for the opening and closing of the leaf stomata
What is osmosis?
300
Sugar sources
What are where sugar is stored or used
400
Explain how cohesion and adhesion work together to bring water up the xylem.
Cohesion allows the water molecules to stick together creating a string of hydrogen bonds to stretch from the roots to the leaves. Adhesion allows the hydrogen bonds (water molecules) to stick to the cellulose walls of the xylem. Working together water is able to stick together and almost climb up the walls of the xylem.
400
What does the phloem of vascular tissue do?
It transports sucrose and other organic compounds along with water.
400
These two things signal the guard cells to perform osmosis
What are sunlight and carbon dioxide?
400
plants
What will consume its stored carbohydrates when it produces stems and leaves.
500
Compare and contrast tracheids and vessel elements.
Tracheids are long cells with tapered ends and vessel elements are wider and shorter tubes.
500
What is alongside the sieve tubes that may provide proteins and other resources to the sieve-tube members?
Companion cells
500
These conditions cause the guard cells to close the stoma
What are nighttime and significant water loss?
500
Pressure Flow Mechanism
What is the widely accepted theory on what drive the movement of phloem sap.
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