In angiosperms (flowering plants), pollination is the placement or transfer of pollen from an anther to a stigma. The two structures may belong to the same flower or to different flowers. In gymnosperms, pollination is the transfer of pollen from a male cone to a female cone.
Pollination is not the same as fertilization. It is the transfer step that brings pollen to a receptive structure. After transfer, pollen may germinate and grow a pollen tube, which carries sperm cells toward an ovule.
All flashcards
What is pollination?
Pollination is the transfer of pollen to a receptive structure: from anther to stigma in angiosperms, or from a male cone to a female cone in gymnosperms.
What is self-pollination?
It is the transfer of pollen to the stigma of the same flower or another flower on the same plant.
What is cross-pollination?
It is the transfer of pollen from one plant to a flower on a different individual of the same species; it is also called out-crossing.
Why is genetic diversity useful to a plant population?
Diversity makes it more likely that some offspring will have traits that help them survive changing environmental conditions or stress.
What does teosinte illustrate about crop breeding?
Modern corn was developed through generations of breeding from teosinte. The plants look very different, even though their genetic difference is small.
Quiz questions
In gymnosperms, where does pollination transfer pollen?Answer: From a male cone to a female cone.
What does self-incompatibility do in some plants?Answer: It prevents certain pollen from germinating or growing through the style.
In angiosperm double fertilization, what does the second sperm cell fuse with?Answer: The two polar nuclei, forming a cell that develops into endosperm.
How does an aggregate fruit develop?Answer: From multiple carpels in one flower.
Which combination is typical of wind-pollinated flowers?Answer: Abundant lightweight pollen and exposed stigmas.
Based on Biology 2e by Mary Ann Clark, Matthew Douglas, Jung Choi (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.