exine The outer, decay-resistant coat of a pollen grain or spore. The exine is characteristic for different plant families and genera, and sometimes even for different species. Hence it forms the basis for the identification and quantitative analysis of the vegetation composition of peats and other suitable sedimentary deposits dating back many thousands of years. See also PALYNOLOGY and POLLEN ANALYSIS.

exine The outer, decay-resistant coat of a pollen grain or spore, composed of sporopollenin, an inert polymer (possibly the toughest of all polymers of biological origin). The exine is characteristic for different plant families and genera, and sometimes even for different species. Hence it forms the basis for the identification and quantitative analysis of the vegetation composition of peats and other suitable sedimentary deposits dating back many thousands of years. See also palynology.

exine Outer, decay-resistant coat of a pollen grain or spore, composed of sporopollenin, an inert polymer. The exine is characteristic for different plant families and genera, and sometimes even for different species. Hence it forms the basis for the identification and quantitative analysis of the vegetation composition of peats and other suitable sedimentary deposits dating back many thousands of years. See also PALYNOLOGY.

exine See pollen.