How does carbon dioxide enter a leaf?
- CO2 is moved by active transport into the leaf by special cells called guard cells.
- CO2 passes through openings called stomata on the leaf surface.
- CO2 diffuses through the epidermal cells into the mesophyll.
- CO2 travels dissolved in the water in the xylem.
- Atmospheric pressure forces CO2 through pits on the leaf surface.
CO2 passes through openings called stomata on the leaf surface.
Secondary growth NEVER occurs in _____.
- stems and leaves
- roots and leaves
Vascular cambium is lateral meristem that provides cells for secondary growth.
Vascular cambium forms wood toward the stem's _____ and secondary phloem toward the stem's _____.
- surface ... center
- center ... center
- surface ... surface
- top ... bottom
- center ... surface
center ... surface
Wood, or secondary xylem, is formed toward the stem's center, and secondary phloem is formed toward the stem's surface.
What is the function of cork?
- regulating the opening and closing of stomata
- providing a site for photosynthesis
- providing cells for primary growth
- providing cells for secondary growth
- insulation and waterproofing
insulation and waterproofing
Cork insulates and waterproofs roots and stems.
How is the supply of vascular cambium maintained?
- by the differentiation of apical meristem
- by the differentiation of secondary xylem
- by the division of its cells
- by the differentiation of cork
- by the differentiation of secondary phloem
by the division of its cells
When a vascular cambium cell divides, one cell differentiates and the other cell remains meristematic.
In a dicot stem, the ________ is between the vascular cambium and the cork cambium.
- vascular cambium
- vascular cylinder
Which of these tissues is between the epidermis and the vascular bundle in a young dicot stem?
- ground tissue
Which of the following makes up most of an old tree trunk?
- secondary xylem
- primary phloem
- meristem tissue
- primary xylem
- secondary phloem
In leaves, chloroplasts are found in _____.
- palisade mesophyll
Both the palisade and spongy mesophyll contain chloroplasts.
Most of a carrot, a root adapted for carbohydrate storage, is:
The location of the pericyle is best described as:
- the outermost layer of the vascular cylinder.
- just beneath the epidermis.
- adjacent to the apical meristem.
- lining the cells of the endodermis.
- between layers of primary xylem and primary phloem.
the outermost layer of the vascular cylinder.
Under the influence of hormones, branch roots emerge from the ________ of a growing root.
- central cylinder
- Casparian strip
On the tip of the root, the apical meristem forms the ________, which prevents the meristem from being worn away as it pushes through the soil.
- root cap
You found the following plants growing on campus during a field trip: a small plant with a notable absence of root hairs; a short, stubby plant with an enlarged taproot; a tall annual herb with fungal strands extending from its roots; a low-growing plant with nodules on the roots; and a woody shrub with an extensive fibrous root system.
Based on this scenario, which plant is most likely a legume with nitrogen-fixing bacteria?
- the woody shrub with the fibrous root system
- the plant with the root nodules
- the plant with no root hairs
- the plant with the enlarged taproot
- the annual herb with the fungal-root association
the plant with the root nodules
The concentration of nutrients in plants is approximately the same as the concentration of nutrients in the surrounding soil.
Diffusion doesn't require energy. Why do plants expend energy in active transport to transport minerals into root hairs?
- Minerals are strongly attracted to soil particles.
- Mineral concentrations in the soil are too high for diffusion.
- Minerals are too large for diffusion.
- Mineral concentrations in the soil are too low for diffusion.
Mineral concentrations in the soil are too low for diffusion.
All of the following are part of a plant's shoot system EXCEPT:
What cellular feature allows a mineral such as manganese to diffuse from cell to cell after being taken up by roots?
- secondary cell walls
- sieve plates
Bacteria-containing nodules in the roots of legume plants aid in the utilization of:
- trace elements.
- carbon dioxide.
Water flows upward in some xylem tubes and downward in others.
The ________ theory explains the movement of water and minerals through xylem.
- bulk-flow theory
- assisted diffusion theory
- cohesiontension theory
- translocation theory
- pressure-flow theory
In the cohesion-tension theory, "cohesion" refers to the:
- use of water in photosynthesis, resulting in a shortage of water in the leaf.
- tendency of water molecules to be attracted to minerals in the water.
- attraction of water molecules for one another.
- evaporation of water from the stomata of the leaf.
- process of osmosis that pulls water into the root.
attraction of water molecules for one another.
When potassium ion is transported into guard cells, water:
- enters by osmosis.
- is actively transported out of the cells.
- moves to the edge of the cell.
- leaves by osmosis.
- is actively transported into the cells.
enters by osmosis.
Which of these processes is responsible for leaves being considered sugar sources?
- Krebs cycle
- citric acid cycle
Leaves produce sugar via photosynthesis.
_____ transport(s) sugars from leaves to, for example, taproots.
- Blood vessels
- Vessel elements
Phloem is responsible for the transport of sugars.
Sugar moves from leaves into the _____ of _____ by _____.
- sieve-tube members ... xylem ... active transport
- tracheids ... phloem ... diffusion
- tracheids ... phloem ... active transport
- sieve-tube members ... phloem ... active transport
- sieve-tube members ... phloem ... diffusion
sieve-tube members ... phloem ... active transport
The water pressure that pushes water and sugar from sugar source to sugar sink is referred to as _____.
- bulk flow
- solute pressure
- root pressure
Bulk flow is the force responsible for the translocation that occurs in phloem.
Water moves into phloem by _____.
- root pressure
- active transport
Water moves down its concentration gradient into phloem by osmosis.
At a sugar sink, sugar is removed from phloem by _____.
- root pressure
- active transport
Active transport moves sugar from phloem into a sugar sink.
In a sugar sink, such as a taproot, sugar is converted into _____.
- fatty acids
_____ is responsible for the movement of sugars from leaves to taproots; _____ is responsible for the movements of sugar from taproots to leaves.
- Bulk flow ... bulk flow
- Bulk flow ... root pressure
- Root pressure ... bulk flow
- Bulk flow ... transpiration
- Transpiration ... transpiration
Bulk flow ... bulk flow
Tree roots are a ________ of sugars in spring and a ________ in the fall.
- source; source
- sink; sink
- sink; source
- source; sink
Haven't found what you need?
Search for quizzes and test answers now