Archive for the ‘health’ tag
Tobacco plants change pollinators to ditch worms
Sure, the hawkmoth does a good job of pollinating the plant, Nicotiana attenuata, which grows in the Western United States and flowers at night. But the hawkmoth has this annoying habit of leaving behind its eggs, which develop into caterpillars that like nothing better than to eat the plant.
So N. attenuata strikes back in a novel way, according to scientists at the Max Planck Institute for Chemical Ecology in Jena, Germany. As they describe in Current Biology, it shifts the time of its flowering to mornings and attracts a different pollinator, a hummingbird. (NYT Science, Plant switches pollinators when caterpillars strike)
Algae protein protects plants from too much sun
Photosynthetic organisms need to cope with a wide range of light intensities, which can change over timescales of seconds to minutes. Too much light can damage the photosynthetic machinery and cause cell death. Scientists at the Carnegie Institution were part of a team that found that specific proteins in algae can act as a safety valve to dissipate excess absorbed light energy before it can wreak havoc in cells.
The research, performed mostly by Graham Peers in the laboratory of Krishna Niyogi from the University of California, Berkeley, included researchers at the University of Münster, Germany, and used a mutant strain of the single-celled green alga Chlamydomonas reinhardtii, originally isolated at the Carnegie Institution, to show that a specific protein of the light harvesting family of proteins plays a critical role in eliminating excess absorbed light energy. A mutant lacking this protein, designated LHCSR, suffered severely when exposed to fluctuating light conditions. “Photosynthetic organisms must be able to manage absorbed light energy,” says study co-author Arthur Grossman of Carnegie’s Department of Plant Biology, “and the LHCSR proteins appear to be critical for algae to eliminate absorbed light energy as heat as light levels in the environment fluctuate, becoming potentially toxic.”
read more . . . Safety valve protects photosynthesis from too much sun
More information
Nature Conversion of Light into Chemical Energy in Photosynthesis ( pdf $)
Lack of solar wind increases tree growth
A group of researchers at the University of Edinburgh found that Galactic Cosmic Rays cause trees to grow faster.
The sun has an 11 year cycle of solar spots, when there is a lull in sunspots there is a lull in solar wind. The solar wind protects us from GCRs by creating a magnetic repellent.
When the solar wind is low and Galactic Cosmic Rays arrive on earth in larger numbers, trees grow faster. While we don’t know why it might have something to do with weather changes such as increased cloud cover that forms when the rays are hitting earth.
More information:
Galactic Cosmic Rays
BBC Cosmic pattern to UK tree growth
Solar Cycle Linked to Global Climate
Cosmic rays speed up tree growth
A relationship between galactic cosmic radiation and tree rings ( paper $ )
