These plants photosynthesize deep in the Arctic, even when there is no light
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Most of life engines work in sunlight. Photons are filtered through the atmosphere and eagerly absorbed by light organisms such as plants and algae. Through photosynthesis, the particles of light power cell reaction that produces chemical energy (in the form of sugars), which is then transmitted around the food network in a complex dance from herbivores, predators, cleaners, decayers and others.
On a bright, sunny day there is a wealth of photons to go around. But what happens in low light? Biologists have long been curious about how light photosynthesis can work – or how much photon they need to arrive and how quickly the cell’s photosynthetic machine to process carbon dioxide in oxygen and energy. The calculations suggest a theoretical minimum of about 0.01 micromol photons per square meter per second or less than one hundred thousand of the light on a sunny day.
For decades, this calculation has been theoretical, given the difficulties in studying photosynthesis in low light. No one could confirm it in the field, although there are many places on Earth that light barely reaches. Every winter in the high Arctic, for example, the sun, hidden from the slope of the earth, disappears for months. Meters of snow blanket sea ice and blocks the incoming light, leaving the frigid ocean as dark as the inside of the tomb. There, biologists have guessed photosynthetic microalgae that live in the water and the icy power supply for the season and wait for heat and light to be returned.
“People thought of the polar night like these desert conditions where there is very little life, and things sleep and winter and wait for next spring to come,” said Clara HopeBiogechimist at the Alfred Vegener Institute in Germany. “But really people have never watched it.”
In the winter 2020, Hope spends months of life on a ship inserted into Ice Floa, on the polar night to study the limits of photosynthesis in the dark. The latest survey of her team at Nature Communications reports microvalgae grows and reproduces At the levels of light at or near the theoretical minimum – further more than it has been observed in nature.
The study shows that in some of the most cold, darkest places on Earth, life blooms with the largest Quan of light. “At least some phytoplankton, under some conditions, can be able to do some very useful things in very weak light,” said Douglas CampbellWater photosynthesis specialist at Mount Alison University in Canada, who did not participate in the study. “This is an important job.”
The power of the dark side
Scientists have traditionally learned that the Arctic is a place for stagnation during the bigger part of the year. In winter, organisms that can escape from frigid waters do so; Those who remain live from stored reserves or sink in a silent sleep. Then, when the sun returns, the place returns to life. During spring flowering, enhancing the photosynthesis of algae and other germs, the Arctic ecosystem is launched, nourishing annually cheerful, with tiny crustaceans, fish, seals, birds, polar bears, whales and more.
It seemed that any phytoplankton could get a worse start than the race could have a more successful summer. This made her wonder when exactly the organisms could respond to the light that returns.
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