Foldable structures and the natural design of pollen grains

被引:245
作者
Katifori, Eleni [1 ,2 ]
Alben, Silas [3 ,4 ]
Cerda, Enrique [5 ]
Nelson, David R. [1 ,3 ]
Dumais, Jacques [6 ]
机构
[1] Harvard Univ, Dept Phys, Cambridge, MA 02138 USA
[2] Rockefeller Univ, Ctr Studies Phys & Biol, New York, NY 10065 USA
[3] Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA
[4] Georgia Inst Technol, Sch Math, Atlanta, GA 30332 USA
[5] Univ Santiago Chile, Dept Fis, Santiago, Chile
[6] Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA
基金
美国国家科学基金会;
关键词
harmomegathy; inextensional deformation; thin shell theory; elasticity; ANGIOSPERM POLLEN; SURFACES;
D O I
10.1073/pnas.0911223107
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
Upon release from the anther, pollen grains of angiosperm flowers are exposed to a dry environment and dehydrate. To survive this process, pollen grains possess a variety of physiological and structural adaptations. Perhaps the most striking of these adaptations is the ability of the pollen wall to fold onto itself to prevent further desiccation. Roger P. Wodehouse coined the term harmomegathy for this folding process in recognition of the critical role it plays in the survival of the pollen grain. There is still, however, no quantitative theory that explains how the structure of the pollen wall contributes to harmomegathy. Here we demonstrate that simple geometrical and mechanical principles explain how wall structure guides pollen grains toward distinct folding pathways. We found that the presence of axially elongated apertures of high compliance is critical for achieving a predictable and reversible folding pattern. Moreover, the intricate sculpturing of the wall assists pollen closure by preventing mirror buckling of the surface. These results constitute quantitative structure-function relationships for pollen harmomegathy and provide a framework to elucidate the functional significance of the very diverse pollen morphologies observed in angiosperms.
引用
收藏
页码:7635 / 7639
页数:5
相关论文
共 26 条
[1]  
[Anonymous], 2004, POLLEN HIDDEN SEXUAL
[2]  
[Anonymous], COMPTES RENDUS ACAD
[3]  
Blackmore S., 1986, POLLEN SPORES FORM F, P137
[5]  
DIRK JS, 1957, LECT CLASSICAL DIFFE
[6]  
DONALD EA, 2003, J EXP BOT, V54, P2307
[7]   How the Venus flytrap snaps [J].
Forterre, Y ;
Skotheim, JM ;
Dumais, J ;
Mahadevan, L .
NATURE, 2005, 433 (7024) :421-425
[8]   Principal modes of infoldings in tricolp(or)ate Angiosperm pollen [J].
Halbritter, H ;
Hesse, M .
GRANA, 2004, 43 (01) :1-14
[9]   POLLEN WALLS AS ADAPTIVE SYSTEMS [J].
HESLOPHARRISON, J .
ANNALS OF THE MISSOURI BOTANICAL GARDEN, 1979, 66 (04) :813-829
[10]   INTERPRETATION OF THE HYDRODYNAMICS OF POLLEN [J].
HESLOPHARRISON, J .
AMERICAN JOURNAL OF BOTANY, 1979, 66 (06) :737-743