What is the evolutionary significance of the 'pollen tube' in Phanerogams?
Show answer and explanation
Correct answer: It removes the need for external water in fertilization.
The development of the pollen tube (siphonogamy) allowed sperm to be delivered directly to the egg. This freed seed plants from needing a film of water for motile sperm, enabling them to colonize diverse terrestrial habitats.
Keep practicing
More Evolution of Seeds questions
- In the evolution of the ovule, the 'micropyle' serves what primary purpose?
- The transition from a megaspore-dispersing ancestor to a seed-bearing plant involved the reduction of the number of functional megaspores p…
- Which group of extinct plants is often referred to as 'Pteridosperms'?
- The protective 'seed coat' develops from which part of the ovule?
- What major advantage do seeds have over spores for plant survival?
- Which primitive gymnosperm order is considered a 'living link' in the evolution of seeds due to its motile sperm?