Question

Make a list of any three out breeding devices that flowering plants have developed and explain how they help to encourage cross-pollination?

Answer 1

Three outbreeding devices that flowering plants have developed:
Receptivity of stigma and release of the pollen grain is not synchronized, i.e., stigma becomes receptive much before pollens are released or after they are released to avoid self-pollination.

Self-incompatibility: A genetic method to prevent pollens from fertilizing ovules of the same flower by inhibiting their germination on stigma or pistil.

Production of unisexual flowers: So that the male and female parts will be present on different plants i.e., dioecious or on different flowers in the same plant (monoecious). This prevents both autogamy and geitonogamy.