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 Lungs Design And Purpose Main Article |  Glossary |  Lungs Design And Purpose Index 

Lungs Design And Purpose Glossary of Terms

The following are health and medical definitions of terms that appear in the Lungs Design And Purpose article.

Abdominal: Relating to the abdomen, the belly , that part of the body that contains all of the structures between the chest and the pelvis . The abdomen is separated anatomically from the chest by the diaphragm , the powerful muscle spanning the body cavity below the lungs .
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Abdominal cavity: The cavity within the abdomen, the space between the abdominal wall and the spine.
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Accessory: Additional, extra, supplementary, subsidiary to the main thing. An accessory digestive organ is an organ that helps with digestion but is not part of the digestive tract. The accessory nerve is so-called because it receives an additional (accessory) root from the upper part of the spinal cord. An accessory placenta is an extra placenta separate from the main placenta.

Adjacent: Lying nearby. Related terms include superjacent, subjacent, and circumjacent. From ad-, near + the Latin jacere, to lie = to lie near.

Alveoli: The plural of alveolus. The alveoli are tiny air sacs within the lungs where the exchange of oxygen and carbon dioxide takes place.

Artery: A vessel that carries blood high in oxygen content away from the heart to the farthest reaches of the body. Since blood in arteries is usually full of oxygen, the hemoglobin in the red blood cells is oxygenated. The resultant form of hemoglobin (oxyhemoglobin) is what makes arterial blood look bright red.
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Blood: The familiar red fluid in the body that contains white and red blood cells, platelets, proteins, and other elements. The blood is transported throughout the body by the circulatory system. Blood functions in two directions: arterial and venous. Arterial blood is the means by which oxygen and nutrients are transported to tissues while venous blood is the means by which carbon dioxide and metabolic by-products are transported to the lungs and kidneys, respectively, for removal from the body.

Breathing: The process of respiration, during which air is inhaled into the lungs through the mouth or nose due to muscle contraction, and then exhaled due to muscle relaxation.

Bronchi: The large air tubes leading from the trachea to the lungs that convey air to and from the lungs. The bronchi have cartilage as part of their supporting wall structure. The trachea divides to form the right and left main bronchi which, in turn, divide to form the lobar , segmental, and finally the subsegmental bronchi.
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Capillaries: Capillaries are the smallest of blood vessels. They serve to distribute oxygenated blood from arteries to the tissues of the body and to feed deoxygenated blood from the tissues back into the veins. The capillaries are thus a central component in the circulatory system, essentially between the arteries and the veins. When pink areas of skin are compressed, this causes blanching because blood is pressed out of the capillaries. The blood is the fluid in the body that contains, among other elements, the red blood cells (erythrocytes) that carry the oxygen and give the blood its red color.

Capillary: One of the tiny blood vessels that connect the arterioles (the smallest divisions of the arteries) and the venules (the smallest divisions of the veins). The capillaries form a fine network in many parts of the body.
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Carbon dioxide: A gas which is the byproduct of cellular metabolism and which collects in the tissues, is cleared from the tissues by the blood within the veins, is carried by the hemoglobin in the red blood cells, and removed from the body via the lungs in the exhaled air. Abbreviated CO2.

Cavities: Holes in the two outer layers of a tooth called the enamel and the dentin. The enamel is the outermost white hard surface and the dentin is the yellow layer just beneath enamel. Both layers serve to protect the inner living tooth tissue called the pulp, where blood vessels and nerves reside. Small cavities may not cause pain, and may be unnoticed by the patient. Larger cavities can collect food, and the inner pulp of the affected tooth can become irritated by bacterial toxins, foods that are cold, hot, sour, or sweet - causing toothache. Also referred to as caries.

Cell: The basic structural and functional unit in people and all living things. Each cell is a small container of chemicals and water wrapped in a membrane .
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Chest: The area of the body located between the neck and the abdomen . The chest contains the lungs , the heart and part of the aorta . The walls of the chest are supported by the dorsal vertebrae , the ribs , and the sternum .
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Cilia: The fine hairlike projections from certain cells such as those in the respiratory tract that sweep in unison and help to sweep away fluids and particles. Some single-celled organisms use the rhythmical motion of cilia for locomotion .
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Circulation: The movement of fluid in a regular or circuitous course. Although the noun "circulation" does not necessarily refer to the circulation of the blood, for all practical purposes today it does. Heart failure is an example of a problem with the circulation.

Coma: A state of deep unarousable unconsciousness.
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Contraction: The tightening and shortening of a muscle.

Gas exchange: The primary function of the lungs involving the transfer of oxygen from inhaled air into the blood and the transfer of carbon dioxide from the blood into the exhaled air.

Heart: The muscle that pumps blood received from veins into arteries throughout the body. It is positioned in the chest behind the sternum (breastbone; in front of the trachea, esophagus, and aorta; and above the diaphragm muscle that separates the chest and abdominal cavities. The normal heart is about the size of a closed fist, and weighs about 10.5 ounces. It is cone-shaped, with the point of the cone pointing down to the left. Two-thirds of the heart lies in the left side of the chest with the balance in the right chest.
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Lungs: The lungs are a pair of breathing organs located with the chest which remove carbon dioxide from and bring oxygen to the blood. There is a right and left lung.

Membrane: A very thin layer of tissue that covers a surface.

Microscopic: So small it cannot be seen without the aid of microscope. As opposed to macroscopic (large enough to be seen with naked eye). A tiny tumor is microscopic while a big tumor is macroscopic.
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Mouth: 1. The upper opening of the digestive tract, beginning with the lips and containing the teeth, gums, and tongue. Foodstuffs are broken down mechanically in the mouth by chewing and saliva is added as a lubricant. Saliva contains amylase, an enzyme that digests starch. 2. Any opening or aperture in the body. The mouth in both senses of the word is also called the os, the Latin word for an opening, or mouth. The o in os is pronounced as in hope. The genitive form of os is oris from which comes the word oral.

Mucus: A thick slippery fluid produced by the membranes lining certain organs such as the nose, mouth, throat, and vagina. Mucus is the Latin word for "a semifluid, slimy discharge from the nose." Note that mucus is a noun while the adjective is mucous.

Muscle: Muscle is the tissue of the body which primarily functions as a source of power. There are three types of muscle in the body. Muscle which is responsible for moving extremities and external areas of the body is called "skeletal muscle." Heart muscle is called "cardiac muscle." Muscle that is in the walls of arteries and bowel is called "smooth muscle."

Muscular: Having to do with the muscles. Also, endowed with above average muscle development. Muscular system refers to all of the muscles of the body collectively.

Neck: The part of the body joining the head to the shoulders. Also, any narrow or constricted part of a bone or organ that joins its parts as, for example, the neck of the femur bone.
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Nose: The external midline projection from the face.
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Oxygen: A colorless, odorless and tasteless gas that makes up about 20% of the air we breathe (and at least half the weight of the entire solid crust of the earth) and which combines with most of the other elements to form oxides. Oxygen is essential to human, animal and plant life.
See the entire definition of Oxygen

Pulmonary: Having to do with the lungs. (The word comes from the Latin pulmo for lung).

Red blood cell: The blood cell that carries oxygen. Red cells contain hemoglobin and it is the hemoglobin which permits them to transport oxygen (and carbon dioxide). Hemoglobin, aside from being a transport molecule, is a pigment. It gives the cell its red color (and name).
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Red blood cells: The blood cells that carry oxygen. Red cells contain hemoglobin and it is the hemoglobin which permits them to transport oxygen (and carbon dioxide). Hemoglobin, aside from being a transport molecule, is a pigment. It gives the cells their red color (and their name).
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Respiration: 1. The act of inhaling and exhaling air in order to exchange oxygen for carbon dioxide. Synonymous with breathing and ventilation. 2. The cellular metabolic process by which oxygen is taken in, substances are oxidized, energy is released, and carbon dioxide and oxidized products are given off.

Respiratory: Having to do with respiration, the exchange of oxygen and carbon dioxide. From the Latin re- (again) + spirare (to breathe) = to breathe again.

Respiratory system: The organs that are involved in breathing. These include the nose, throat, larynx, trachea, bronchi, and lungs.

Temperature: The temperature is the specific degree of hotness or coldness of the body. It is usually measured with a thermometer.
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Trachea: A tube-like portion of the breathing or "respiratory" tract that connects the "voice box" (larynx) with the bronchial parts of the lungs.


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Tubes: The "tubes" are medically known as the Fallopian tubes. There are two Fallopian tubes, one on each side, which transport the egg from the ovary to the uterus (the womb). The Fallopian tubes have small hair-like projections called cilia on the cells of the lining.
See the entire definition of Tubes

Windpipe: The trachea, a tube-like portion of the respiratory (breathing) tract that connects the larynx (the voicebox) with the bronchial parts of the lungs.


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 Lungs Design And Purpose Main Article |  Glossary |  Lungs Design And Purpose Index 




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Lungs Design And Purpose

What is COPD?

Chronic obstructive pulmonary disease (COPD) is comprised primarily of two related diseases - chronic bronchitis and emphysema. In both diseases, there is chronic obstruction of the flow of air through the airways and out of the lungs, and the obstruction generally is permanent and progressive over time.

Asthma also is a pulmonary disease in which there is obstruction to the flow of air out of the lungs, but unlike chronic bronchitis and emphysema, the obstruction in asthma usually is reversible. Between "attacks" of asthma the flow of air through the airways usually is good.

There are exceptions, however. In some patients with COPD the obstruction can be partially reversed by medications that enlarge or dilate the airways (bronchodilators) as with asthma. Conversely, some patients with asthma can develop permanent airway obstruction if chronic inflammation of the airways leads to scarring and narrowing of the airway...

Read the Chronic Obstructive Pulmonary Disease article »










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