[Campbell Biology P.678] The development of a dominant sporophyte generation and the evoluti... | Practice Question

The development of a dominant sporophyte generation and the evolution of vascular tissues xylem and phloem in early plants were significant evolutionary milestones. How did these adaptations primarily contribute to the successful colonization of terrestrial environments by vascular plants?

  • A: They enabled plants to grow taller, effectively compete for sunlight, and access resources from a larger volume of soil.
  • B: They eliminated the need for water in sexual reproduction, allowing plants to colonize much drier habitats.
  • C: They led to the immediate development of true roots and seeds, providing superior anchorage and offspring protection.
  • D: They allowed for the direct absorption of CO2 from the soil through specialized rhizoids, improving photosynthetic efficiency.

Explanation

The evolution of a dominant sporophyte generation allowed for larger, more complex plant bodies. Vascular tissues xylem and phloem provided the necessary internal transport system and structural support with lignin in xylem to enable plants to grow much taller than bryophytes. This height advantage was crucial for competing for sunlight and accessing resources from a wider area, leading to the formation of the first forests and successful terrestrial colonization.