Biology Plant Reproduction and Structure Flashcards

Which of the following is an adaptation that helps plants avoid self-pollination?

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.

The transfer of pollen from the anther of one flower to the stigma of a flower on a different plant is called:

Answer: Cross-pollination

Cross-pollination (allogamy) involves pollen transfer between different individuals, increasing genetic diversity in the offspring.

Cleistogamous flowers are unusual because they:

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.

Which of the following correctly pairs a fruit type with its means of dispersal?

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.

Cork (bark) in woody plants is produced by which meristem?

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.

Annual rings visible in tree cross-sections result from differences in wood produced during:

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.

Which of the following modifications represents a stem that has been adapted for water storage in desert plants (succulents)?

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.