Pollen often travels long distances after leaving a plant and is exposed to dry conditions that can desiccate and kill its miniscule grains. Although pollen grains are diverse, all have a cellular wall consisting of an impermeable outer layer called the exine, interrupted by permeable apertures that provide routes of exchange with the external environment. To prevent desiccation, the pollen surface undergoes a folding process called harmomegathy, which results in a sealed pollen grain with the permeable'apertures tucked inside the exine. Eleni Katifori et al. (pp. 7635-7639) used computer modeling, mathematical analysis, and scanning electron microscopy to develop a model of pollen folding.
展开▼
