Angiosperm Functional Organization Practice Quiz (11 questions)

1. Which structures make up the vegetative apparatus of a flowering plant?

A. Leaves, fruits, and seeds

B. Roots, stem, and leaves

C. Stem, flowers, and seeds

D. Roots, flowers, and fruits

Answer: (B)

Explanation

The vegetative apparatus consists of the plant’s roots, stem, and leaves. Flowers, fruits, and seeds are reproductive structures, not components of this apparatus.

2. How can root anchorage both benefit a plant and limit its response to environmental conditions?

A. It improves mineral nutrition but allows the plant to relocate during drought.

B. It helps resist wind but makes the plant unable to move away from environmental constraints.

C. It increases water uptake but prevents the plant from producing leaves.

D. It supports photosynthesis but makes the plant more vulnerable to wind.

Answer: (B)

Explanation

Root anchorage helps a plant resist wind, but the same attachment leaves it immobile when environmental conditions become unfavorable. Greater water uptake is a separate root function and does not explain this mobility trade-off.

3. Why do fine roots and elongated root hairs near root tips improve a plant’s access to soil resources?

A. They provide a larger surface for exchanging gases with the air.

B. They release organic matter that feeds soil fungi.

C. They increase contact with soil water and minerals.

D. They strengthen the root system against wind-driven movement.

Answer: (C)

Explanation

Fine roots and numerous elongated root hairs increase the area in contact with soil water and minerals. Their key role here is not gas exchange with air, which is associated mainly with leaves.

4. In a mycorrhizal association, what does each partner contribute to the exchange?

A. The plant supplies organic matter made in its leaves, while the fungus expands uptake of water and mineral salts.

B. The plant supplies water and mineral salts, while the fungus produces organic matter in its leaves.

C. The fungus supplies water and mineral salts, while the plant expands the fungus’s exchange surface.

D. The fungus supplies leaf-made organic matter, while the plant expands uptake of water and mineral salts.

Answer: (A)

Explanation

The plant provides the fungus with organic matter produced in its leaves, while the fungus increases the plant’s water and mineral-salt uptake by expanding the exchange surface. Reversing which partner supplies organic matter is a plausible mix-up, but organic matter comes from the plant.

5. What is a stoma in a leaf?

A. An epidermal opening, usually bounded by two guard cells, that enables gas exchange with the atmosphere

B. A chlorophyll-bearing cell that captures light energy for photosynthesis

C. A waxy outer layer that reduces water loss from the leaf surface

D. A vascular passage that transports water and mineral salts toward the leaf

Answer: (A)

Explanation

A stoma is an opening in the epidermis, usually bordered by two guard cells, through which gases can pass between the leaf and the atmosphere. The waxy cuticle is a plausible distractor, but it limits water loss rather than serving as the gas-exchange opening.

6. What structural feature distinguishes the cells that make up xylem vessels?

A. They are elongated living cells with cellulose walls and perforated transverse walls.

B. They are elongated dead cells with cellulose walls and perforated transverse walls.

C. They are elongated dead cells with lignin-reinforced lateral walls.

D. They are compact living cells with lignin-reinforced transverse walls.

Answer: (C)

Explanation

Xylem consists of files of elongated dead cells, with remaining lateral walls reinforced by lignin. The description of living cells with cellulose walls and perforated transverse walls instead identifies phloem.

7. What is the main protective function of thick, impermeable bud scales and down during winter?

A. They reduce cold exposure and help buds survive until spring growth.

B. They allow buds to continue photosynthesis under snow cover.

C. They promote leaf shedding by accelerating water loss from buds.

D. They increase water uptake from frozen soil during dormancy.

Answer: (A)

Explanation

Thick, impermeable scales and down protect buds from cold so they can produce leaves in spring. Underground buds also avoid exposure, but their position is a separate protective strategy.

8. How do primary and secondary meristems differ in the type of plant growth they drive?

A. Primary meristems differentiate leaves and flowers, while secondary meristems produce new roots and buds.

B. Primary meristems increase stem and root width, while secondary meristems increase length in many shrubs and trees.

C. Primary meristems increase stem and root length, while secondary meristems increase width in many shrubs and trees.

D. Primary meristems elongate individual cells, while secondary meristems multiply cells at stem and root tips.

Answer: (C)

Explanation

Primary meristems drive lengthwise growth, whereas secondary meristems contribute to growth in width in many shrubs and trees. The reversed option assigns lengthwise growth to secondary meristems and width growth to primary meristems.

9. What can happen to axillary buds when the shoot apex is removed?

A. They form secondary roots because auxin concentrations increase in the buds.

B. They bend toward light because the remaining stem produces uneven cytokinin levels.

C. They stop growing because root-produced cytokinins are no longer available.

D. They can develop and take over growth as the apex’s influence is removed.

Answer: (D)

Explanation

Removing the shoot apex allows axillary buds to take over growth, counteracting the apex’s influence. Root-produced cytokinins promote their development, while auxin from shoot apices opposes it.

10. A gardener wants to improve a plant’s mineral nutrition and support its photosynthesis. Which practical measure best uses the role of roots?

A. Shade the roots so they can capture light and exchange gases with the air

B. Prune the roots so the stem can transport more elaborated sap to the leaves

C. Maintain healthy roots so they can absorb water and mineral ions from the soil

D. Remove the roots so the leaves can absorb mineral ions directly from the soil

Answer: (C)

Explanation

Roots absorb water and mineral ions from the soil, supplying mineral nutrition that plants need for life and photosynthesis. Pruning roots would reduce this uptake rather than increase the transport of elaborated sap.

11. Which feature defines a mycorrhiza?

A. A lasting, mutually beneficial association between a plant root and a fungus of another species

B. A shared root system formed by two plants of the same species

C. A partnership between roots and soil bacteria that produces chlorophyll

D. A temporary interaction in which a fungus parasitizes a plant leaf

Answer: (A)

Explanation

A mycorrhiza is an intimate, lasting, mutually beneficial association between a plant root and a fungus of a different species. A parasitic interaction is not the mutualistic root–fungus partnership described here.