The bark of a tree is impervious to gases and water because bark cells are dead cells of the epidermis and compactly arranged without intercellular spaces. They contain a chemical called suberin in their walls that make them impervious to gases and water and it doesn't allow gases or water into the tree as bark cells are in the bark outer most layer of the tree.
Semi permeable means that some things can go in and out of the cell, but some cannot. Permeable means it allows things to pass through it, so semi permeable means only some things pass through.
<span> It could be weight loss, decrease in muscle mass, changes in hair or skin, diarrhea, extreme fatigue, difficulty recovering from infection or injury, enlarged liver, edema, drop in blood cell number, and frequent colds.
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More precisely, a specific honey fungus measuring 2.4 miles (3.8 km) across in the Blue Mountains in Oregon is thought to be the largest living organism on Earth. Several species of fungi belong to the Armillaria genus, which is popularly known as honey fungus.
