Plant Structure and Function Quiz
Questions: 16 · 10 minutes
1. A cut celery stalk is placed in colored water. Later, colored lines appear running up the stalk. Which tissue did the colored water mainly travel through?
Cambium
Phloem
Xylem
Epidermis
2. What are stomata?
Vascular bundles that strengthen stems
Root extensions that absorb mineral ions
Reproductive cells produced inside anthers
Adjustable pores that permit gas exchange and water-vapor loss
3. Which plant tissue mainly carries water and dissolved mineral ions upward from the roots?
Phloem
Epidermis
Xylem
Cortex
4. A mature leaf produces sucrose that is transported to a developing fruit. How are the leaf and fruit best described in this transport relationship?
The leaf is a source, and the fruit is a sink.
Both are sources because both contain vascular tissue.
The leaf is a sink, and the fruit is a source.
Both are sinks because both require water.
5. A narrow ring of bark containing phloem is removed from a tree trunk while the inner xylem remains intact. What is most likely to happen first near the cut?
Pollen production increases above the ring because the stem is damaged.
Water immediately stops reaching every leaf because all xylem has been removed.
Mineral ions accumulate below the ring because stomata can no longer open.
Sugars accumulate above the removed ring because downward phloem transport is interrupted.
6. What is the main function of the cellulose cell wall in a plant cell?
It controls which substances enter and leave the cell.
It provides structural support and helps the cell resist excessive expansion.
It stores the cell's genetic information.
It produces sugars using light energy.
7. A desert plant has leaves with an unusually thick waxy cuticle. What advantage does this structure provide?
It reduces water loss from the leaf surface.
It transports sugars more rapidly through the leaf.
It increases the leaf's absorption of mineral ions.
It allows roots to grow directly from the leaf.
8. A seedling loses most of its root hairs during transplanting. Which immediate effect is most likely?
Reduced absorption of water and mineral ions from the soil
Faster movement of sugars out of its leaves
Increased production of pollen grains
Greater gas exchange through the stem
9. After fertilization in a flowering plant, which structure normally develops into the fruit?
The anther
The ovary
The sepal
The stigma
10. The growing tip of a young shoot is removed, and its upward growth slows. Which structure was removed?
A lateral root
The root cap
A mature xylem vessel
The apical meristem
11. A leaf receives weak light but can still carry out some photosynthesis. Which cell structure directly captures that light energy?
The chloroplast
The central vacuole
The mitochondrion
The nucleus
12. A plant wilts even though its soil is moist. A disease has blocked one transport tissue in the stem. Which blockage most directly explains the immediate shortage of water in the leaves?
A blockage of phloem sieve tubes
A blockage of xylem vessels
A reduction in petal pigments
A failure of pollen production
13. A root grows through rough, compact soil. Which structure protects the delicate dividing cells at its advancing tip?
The root epidermis
A lateral root
The root cap
A phloem fiber
14. What is the principal transport function of phloem?
Moving oxygen from leaves to roots
Transporting sugars and other organic substances between sources and sinks
Carrying water only from roots to leaves
Moving pollen from anthers to stigmas
15. Which leaf tissue is usually specialized for high rates of photosynthesis because its cells contain many chloroplasts?
Upper epidermis
Spongy mesophyll air spaces
Leaf vein xylem
Palisade mesophyll
16. During a dry afternoon, a plant's guard cells cause many stomata to close. What is the most direct trade-off?
Mineral absorption increases, but root growth stops.
Sugar transport increases, but xylem flow reverses.
Water loss decreases, but less carbon dioxide can enter the leaf.
Water loss increases, but oxygen uptake decreases.