Picaridin repels insects, ticks and chiggers. It is a synthetic compound first made in the 1980s. It was made to resemble the natural compound piperine, which is found in the group of plants that are used to produce black pepper. Picaridin has been widely used as an insect repellent in Europe and Australia, but has only been available in the United States since 2005.
Plants have run the biological carbon cycle for 3 billion years in the ocean, and for the past 400 million years on land, using the process of photosynthesis to convert atmospheric CO2 into carbon-rich carbohydrates and sugars to feed themselves. And they are very good at it.
Plants pull carbon dioxide from the atmosphere, releasing the  oxygen and retaining the carbon, in a process known as  photosynthesis. Most photosynthesis is performed by ma â¦ rine (ocean)  cyanobacteria.    Plants, trees and forests act as big carbon sinks, provided they do  not burn.arbon dioxide doesn't really hurt the atmosphere. Venus and Mars both have atmospheres comprised primarily of CO2. CO2 is also a necessary constituent of our atmosphere for â¦ plant respiration (photosynthesis) and for keeping the earth warm.