Pollen Tubes: An Excellent Model
Pollen tubes are an excellent model for the understanding of plant cell behavior. They are easily cultivated in vitro and have a very dynamic cytoskeleton that polymerizes at very high rates, providing the pollen tube with interesting mechanical properties. The pollen tube has an unusual kind of growth; it extends exclusively at its apex. Extending the cell wall only at the tip minimizes friction between the tube and the invaded tissue. This tip growth is performed in a pulsating manner rather than in a steady fashion. Remarkably, the pollen tube’s journey through the style often results in depth-to-diameter ratios above 100:1 and up to 1000:1 in certain species, whereas classic mechanical drilling is often only effective up to 15:1 ratios. However, the internal machinery and the external interactions that govern the dynamics of pollen tube growth are far from being fully understood.
Read more about this topic: Pollen Tube
Famous quotes containing the words pollen, excellent and/or model:
“Books are the bees which carry the quickening pollen from one to another mind.”
—James Russell Lowell (1819–1891)
“Alas, poor Yorick! I knew him, Horatio: a fellow of infinite jest, of most excellent fancy.... Where be your jibes now, your gambols, your songs, your flashes of merriment that were wont to set the table on a roar?”
—William Shakespeare (1564–1616)
“The best way to teach a child restraint and generosity is to be a model of those qualities yourself. If your child sees that you want a particular item but refrain from buying it, either because it isn’t practical or because you can’t afford it, he will begin to understand restraint. Likewise, if you donate books or clothing to charity, take him with you to distribute the items to teach him about generosity.”
—Lawrence Balter (20th century)