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.
And the lungs are a core component of this vital task. The lungs are part of the respiratory system, and are divided into lobes or sections. The right lung has three lobes and the left lung has two lobes. You can think of each lobe as a balloon: It inflates when you breathe in and deflates when you breathe out. Each lung sits next to the heart. They are safeguarded by a thin tissue called the pleura. Inside the lungs are millions of tiny air sacs called alveoli. These sacs â about 300 million total â are overlapped or interwoven by capillaries, which are fine blood vessels.