glossary of common forestry terminology . Click letter to advance to that section of the glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z . ACRE â Area of land containing 43,560 square feet. A square 1-acre plot measures 209 feet by 209 feet; a circular acre has a radius of 117.75 feet.
What Are the Lungs? Your lungs are organs in your chest that allow your body to take in oxygen from the air. They also help remove carbon dioxide (a waste gas that can be toxic) from your body. The lungs' intake of oxygen and removal of carbon dioxide is called gas exchange. Gas exchange is part of breathing.
For other uses, see Breathing (disambiguation) . Breathing is the process that moves air in and out of the lungs, or oxygen through other respiratory organs such as gills. For organisms with lungs, breathing is also called ventilation, which includes both inhalation and exhalation. Breathing is one part of physiological respiration required to sustain life.