CLEP Biology Plant Reproduction and Structure 5 — Questions and Answers
Question 1: Which of the following is an adaptation that helps plants avoid self-pollination?
- Dichogamy (maturation of anthers and stigmas at different times) (Correct answer)
- Having both stamens and pistils in the same flower
- Producing nectar to attract pollinators
- Growing in dense, wind-exposed habitats
Correct answer: Dichogamy (maturation of anthers and stigmas at different times)
Dichogamy ensures that pollen is released before or after the stigma of the same flower is receptive, preventing self-fertilization.
Question 2: The transfer of pollen from the anther of one flower to the stigma of a flower on a different plant is called:
- Cross-pollination (Correct answer)
- Self-pollination
- Autogamy
- Cleistogamy
Correct answer: Cross-pollination
Cross-pollination (allogamy) involves pollen transfer between different individuals, increasing genetic diversity in the offspring.
Question 3: Cleistogamous flowers are unusual because they:
- Never open and self-fertilize within the bud (Correct answer)
- Only open at night for moth pollination
- Require two visits from pollinators to be fertilized
- Produce pollen but no ovules
Correct answer: Never open and self-fertilize within the bud
Cleistogamous flowers remain permanently closed and self-fertilize within the bud, guaranteeing seed production without pollinators.
Question 4: Which of the following correctly pairs a fruit type with its means of dispersal?
- Maple samara — wind dispersal (Correct answer)
- Coconut — animal ingestion
- Burdock burr — water dispersal
- Cherry drupe — wind dispersal
Correct answer: Maple samara — wind dispersal
Maple samaras have wing-like extensions (papery outgrowths) that allow them to spin and be carried by wind away from the parent tree.
Question 5: Cork (bark) in woody plants is produced by which meristem?
- Cork cambium (phellogen) (Correct answer)
- Vascular cambium
- Apical meristem
- Intercalary meristem
Correct answer: Cork cambium (phellogen)
The cork cambium (phellogen) is the lateral meristem that produces cork cells (phellem) outward, forming the protective bark of woody plants.
Question 6: Annual rings visible in tree cross-sections result from differences in wood produced during:
- Spring and summer versus fall and winter (Correct answer)
- Day and night
- Periods of drought and flooding
- Active photosynthesis versus respiration
Correct answer: Spring and summer versus fall and winter
Annual rings form because spring wood (large, light-colored xylem cells) differs visibly from late summer wood (smaller, dense, darker cells), marking each year's growth.
Question 7: Which of the following modifications represents a stem that has been adapted for water storage in desert plants (succulents)?
- Fleshy, enlarged stem with reduced leaves (Correct answer)
- Horizontal underground stem (rhizome)
- Enlarged, starchy underground stem (tuber)
- Thin, flattened stem that resembles a leaf (cladode)
Correct answer: Fleshy, enlarged stem with reduced leaves
Many desert succulents like cacti have swollen, fleshy stems specialized for storing large volumes of water and reducing surface area for water loss.
CLEP Biology Plant Reproduction and Structure 5
Which of the following is an adaptation that helps plants avoid self-pollination?