Chapter 36 LSU BIOL 1202 (Pomarico)
Questions and Correct Answers 2025-
2026 Updated.
Plants must always compromise between _____ and _____. - Answer maximizing
photosynthesis ... minimizing water loss
A plant leaf is constructed from a variety of cell types with specialized structures and functions.
Many of the properties of leaf cells facilitate some aspect of water transport.
The diagram below shows a cross section through a leaf.
Drag the labels to the appropriate targets to match the function with the structure indicated in
the diagram. Labels may be used once, more than once, or not at all. - Answer A. cells that
transport water from the roots to the leaves
B. a group of different cell types involved in long-distance transport of water and nutrients
C. cells with a coating that prevents evaporation of water
D. cells with a coating that prevents evaporation of water
E. cells where most evaporation of water in the leaf occurs
F. cells that control the rate of water loss from the leaf
The apoplast and symplast are two regions of the plant that serve as pathways for water and
solute transport over both short and long distances. These pathways are represented by the
arrows in the diagram below, which shows three adjacent cells in a leaf or root.
Sort each statement into the appropriate bin. - Answer Apoplastic Pathway:
- is depicted by the red arrow in the diagram
- involves water transport outside the protoplast
- consists of a porous matrix of hydrophilic monomers
Symplastic Pathway:
- is depicted by the blue arrow in the diagram
- involves water moving via plasmodesmata
- can involve water entering vacuoles
Neither Pathway:
- requires water to cross multiple plasma membranes
, Water follows a specific path as it moves from the xylem in the vein of a leaf to the air outside
the leaf.
Drag the labels into the flowchart to show the sequence of events after water enters a leaf in
the xylem. Not all labels will be used. - Answer a) water exits the xylem and enters the walls
of surrounding cells
b) water spreads as a film in and on the surface of mesophyll cell walls
c) water evaporates from the surface of mesophyll cells
d) water vapors diffuses through the air spaces of the leaf
e) water vapor exits the leaf through the stomata
Transpiration provides the driving force for the movement of water from the soil to the highest
leaves of plants. Transpiration is also linked to other processes in plants, including
photosynthesis and the transport of mineral nutrients.
Which of the following statements correctly describe(s) a relationship between transpiration
and other processes in plants?
Select all that apply. - Answer - Transpiration is important in cooling leaves on warm, sunny
days.
- In most plants, the highest rate of transpiration occurs when the rate of photosynthesis is also
highest.
- Open stomata provide a low-resistance pathway for CO2 to enter and for water to exit the leaf.
- To minimize water loss during dry conditions, most plants must also restrict their ability to
carry out photosynthesis.
The solute most abundant in phloem sap is _____. - Answer sugar
In addition to transporting sugar, the phloem also _____. - Answer all of the above
If ΨP = 0.3 MPa and ΨS = -0.45 MPa, the resulting Ψ is ________. - Answer -0.15 MPa
Questions and Correct Answers 2025-
2026 Updated.
Plants must always compromise between _____ and _____. - Answer maximizing
photosynthesis ... minimizing water loss
A plant leaf is constructed from a variety of cell types with specialized structures and functions.
Many of the properties of leaf cells facilitate some aspect of water transport.
The diagram below shows a cross section through a leaf.
Drag the labels to the appropriate targets to match the function with the structure indicated in
the diagram. Labels may be used once, more than once, or not at all. - Answer A. cells that
transport water from the roots to the leaves
B. a group of different cell types involved in long-distance transport of water and nutrients
C. cells with a coating that prevents evaporation of water
D. cells with a coating that prevents evaporation of water
E. cells where most evaporation of water in the leaf occurs
F. cells that control the rate of water loss from the leaf
The apoplast and symplast are two regions of the plant that serve as pathways for water and
solute transport over both short and long distances. These pathways are represented by the
arrows in the diagram below, which shows three adjacent cells in a leaf or root.
Sort each statement into the appropriate bin. - Answer Apoplastic Pathway:
- is depicted by the red arrow in the diagram
- involves water transport outside the protoplast
- consists of a porous matrix of hydrophilic monomers
Symplastic Pathway:
- is depicted by the blue arrow in the diagram
- involves water moving via plasmodesmata
- can involve water entering vacuoles
Neither Pathway:
- requires water to cross multiple plasma membranes
, Water follows a specific path as it moves from the xylem in the vein of a leaf to the air outside
the leaf.
Drag the labels into the flowchart to show the sequence of events after water enters a leaf in
the xylem. Not all labels will be used. - Answer a) water exits the xylem and enters the walls
of surrounding cells
b) water spreads as a film in and on the surface of mesophyll cell walls
c) water evaporates from the surface of mesophyll cells
d) water vapors diffuses through the air spaces of the leaf
e) water vapor exits the leaf through the stomata
Transpiration provides the driving force for the movement of water from the soil to the highest
leaves of plants. Transpiration is also linked to other processes in plants, including
photosynthesis and the transport of mineral nutrients.
Which of the following statements correctly describe(s) a relationship between transpiration
and other processes in plants?
Select all that apply. - Answer - Transpiration is important in cooling leaves on warm, sunny
days.
- In most plants, the highest rate of transpiration occurs when the rate of photosynthesis is also
highest.
- Open stomata provide a low-resistance pathway for CO2 to enter and for water to exit the leaf.
- To minimize water loss during dry conditions, most plants must also restrict their ability to
carry out photosynthesis.
The solute most abundant in phloem sap is _____. - Answer sugar
In addition to transporting sugar, the phloem also _____. - Answer all of the above
If ΨP = 0.3 MPa and ΨS = -0.45 MPa, the resulting Ψ is ________. - Answer -0.15 MPa
