News tagged with pollen
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Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes (sperm cells). Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the female cone of coniferous plants. When pollen lands on a compatible pistil or female cone (i.e., when pollination has occurred), it germinates and produces a pollen tube that transfers the sperm to the ovule (or female gametophyte). Individual pollen grains are small enough to require magnification to see detail.
For more information about Pollen, read the full article at
Wikipedia.
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Trapped dental 'calculus' holds clues to ancient human diets and health
Many ancient human teeth, including specimens tens of thousands of years old, still hold onto tiny pieces of food -- and even bacteria. Anthropologists are studying the tartar attached to ancient human teeth ...
Other Sciences / Archaeology & Fossils
May 31, 2012 |
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Got nectar? To hawkmoths, humidity is a cue
(Phys.org) -- Humidity emanating from a flower's nectar stores tells a moth if the flower is worth a visit, research led by a UA entomologist has discovered.
May 30, 2012 |
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