what are alveoli and what do they do?
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ALVEOLI:\n The alveoli are the final branchings of the respiratory tree and perform gas exchange for the lung. The thin gas-blood barrier between the alveolar space and the pulmonary capillaries allows for rapid gas exchange. Oxygen and carbon dioxide diffuses through the alveolar epithelium and the capillary endothelium.\n\nThere are two types of alveolar epithelial cells. Type I cells thinly line the alveolar walls. Type II cells produce surfactant - a lubricant that reduces surface tension. \n\nSURFACTANT:\n Surfactant is any substance that acts to alter surface tensions, such as those in the lungs. This substance reduces the surface tension within the alveoli, preventing them from collapsing.\n\nInfant Respiratory Distress Syndrome is caused by a lack of pulmonary surfactant. The alveoli collapse and prevent the infant from breathing properly.
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There are specialized cells (goblet cells) that line all of the mucous membranes of your body: nasal passages, throat, lungs, intestines, urinary tract, eyes, vagina and etc.  These cells are capable of producing and excreting copious amounts of mucus in response to infections, allergies, injuries, stimulation, and  nflammation. Most of the time this mucus you make is  your body's way of protecting and/or healing itself.  Mucus production also helps us rid ourselves of foreign invaders (bacteria, viruses, pollen, dust etc.).  In the case of a cold, plugging up the nose with mucus may help to kill the viruses by blocking the natural "air conditioning" and raising the temperature of the nasal membranes.\n\nMucus is mostly made up of water, proteins and inorganic salts.  Stuff that is readily available to your body, so it is no problem to make plenty.
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Lungs. Same as humans and most land mammals.
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there are several, one is a vacuole. It is used to store soemthing usually food within the cell
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Flinging.  lol j/k\n\nBoogers are made up from all the dirt and debris that the cilia like hairs of the nose collect.  The hairs are a filter keeping infection causing debris out of the lungs.
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The tiniest part of our lung is called alveolus (plural is alveoli). It is like an inflated balloon . The air in side this balloon is the fresh air we have inhaled.\n Now imagine your ten fingers covering an inflated balloon from all the sides. That is how the blood capillaries cover the alveoli . these blood capillaries have extremely thin wall through the oxygen, which is at a higher concentration in the fresh air of the alveoli, diffuses in the blood capillary. It is immediately picked up by the hemoglobin in the Red blood cells forming oxyhemoglobin  . It is the source of oxygen to our body. This is then taken to different parts of the body and given to them.\nAt the same time , CO2 collected from the body parts and brought to the alveoli by those vary capillaries diffuses in to the air of the alveoli because its concentration in the capillaries is greater. \nThe air in the alveoli is now stale air rich in CO2 and poor in O2. It is exhaled out.\nThus , the gaseous exchange can occur only on the surface of the alveoli . Their walls are as thin as the walls of a soap bubble, only that they are not fragile like soap bubble.\nIn the body muscles the gaseous exchange occurs in the same fashion but between the capillaries.
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First, the diaphragm contracts allowing entrance of air into the body. (I'll tell you why and how the diapraghm contracts later.) Oxygen then travels into the several parts of the lungs (I have given them in your other question) until it reaches the alveoli. The alveoli is suurounded by arteries and veins. Oxygen diffuses into the blood cells and is distributed to the different cells in the body. The mitochondria of cells use up the oxygen so as to provide us energy we need. In this process, carbon dioxide is produced. The carbond dioxide are released into the blood stream. It will travel through the blood stream until it reaches the alveoli where the blood cells empty the carbon dioxide into the alveoli to make room for the needed oxygen. When the oxygen is already used up, there will be a high concentration of carbon dioxide in the blood which will somehow raise the blood pH. An impulse is sent to the brain to let it know that the blood pH is increasing and in return, the brain signals the diaphragm to contract to tell the body to gasp for air. This cycle is repeated and is responsible for every breath we take.\n\nI hope I have helped you.
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Generally white saliva or mucous is a normal way for the lungs to keep themselves clean. If it is thick you may be dehydrated. The easiest way to make mucous thinner is to drink water. Water helps thin out the mucous and make it easier for the body to absorb. If you have any color like yellow, green, brown, you might have some kind of infection.
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Surfactants are agents such as a detergent or a drug that reduces the surface tension of liquids so that the liquid spreads out, rather than collecting in droplets.\n\nIn physiology,  they are surface-active lipoprotein substances secreted naturally in the lungs, lack of which causes respiratory problems especially in premature babies
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"intra" alveolar hemorrhage is a medical term which describes how the alveoli, which are the major functioning mechanism in your lungs, are bleeding from inside themselves.  "intrabronchial" hemorrhage is a rupture in the tube or tubes that carry air into each individual lung.  Usually cancer is the reason for this.  The cells inside the lungs are growing too rapidly and expand too wide for normal capacity and rupture inside the infected cells.  It would be interesting to know what the history and symptoms the patient was presenting before the death, or did it just occur randomly.  Also you may want to post a question in the lung section of this site...if they have one, I'm not sure
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It works with each heartbeat.  The gas moves with each heart beat. The area of the lung where the blood takes the gas is called the A/C membrane (Alveolar/Capillary) the membrane is so thin so the gas can diffuse into the blood.
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Difusion is the movement of particles from an area of high concentration to an area of low concentration, until they are apread out evenly.\n\nExamples for diffusion: \nThe alveoli are well adapted for diffusion of gases, \nthey have a large surface area\nthey are moist, so gases can dissolve\nthey have thin walls\nand a good blood supply.\n\nThe small intestine is specialised for absorption. \nIt has: \nA thin lining\na good blood supply\na very large surface area.\n\nOsmosis is the diffusion of water molecules from a dilute solution to a more concentrated solution through a partially permeable membrane.\n\nA partially permeable membrane allows water molecules to pass through, but not solute molecules.\n\nWhen a plant cells are full of water they are turgid.\nThis rigidity or turgour gives the plant support\nCells are able to absorb some substances against a concentration gradient.\n\nActive transport needs energy from respiration. \n\nActive transport....\nNot all sustances pass into cells by diffusion or osmosis. Some substances are absorbed against a concentration gradient. But to do this energy is needed and it comes from respiration. This process is called ACTIVE TRANSPORT.\nExample of active transport are:\nThe uptake of ions by root hair cells from the soil, where they are in very dilute solution;\nthe uptake of sugar molecules into the small intestine;\nthe re-absorbtion of useful ions in the nephrons of the kidneys.
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I just learned this in medical school. \n\nThey are a type of lung cell.\n\nThey compose 95% of the lung wall, but they are less numerous than type II alveolar cells.\n\nThey function as part of the blood/air barrier.
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Lung infiltrates is a term that is used to describe the appearance of any abnormal substance that has accumulated in the lungs.  Lungs usually appear very dark on an xray because they contain mostly air which allows the xrays through very easily.  If the lungs start accumulating fluid or pus, for example, fewer of the xrays will make it through to the film and those areas appear whiter.  The white areas are called infiltrates.  Infiltrates can represent many things including pneumonia and other infections, tuberculosis, pulmonary edema, and hemorrhage, just to name a few.
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The machine that delivers medication like albuterol is called a nebulizer.  It's basically a tiny air compressor that vaporizes the liquid medication so it can be inhaled.
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Pneumonia (say: new-mo-nya) is an infection of one or both lungs. To know what that means, you have to know something about lungs and what they do. When you breathe in, you pull oxygen into your lungs. That oxygen travels through breathing tubes and eventually gets into your blood through the alveoli (say: al-vee-oh-lie). \n\nAlveoli are tiny air sacs covered in tiny blood vessels called capillaries. How can something so small get oxygen into your blood? You have about 600 million of them! When oxygen-rich air reaches the alveoli, it can be absorbed into the blood. Then your red blood cells can carry oxygen all over your body. The body needs oxygen to keep working properly and to stay alive. \n\nBut if a person has pneumonia, his or her lungs can't do this important job very well. Why? Because this kind of infection creates fluid that blocks the alveoli. This makes it hard for oxygen to get deep into the lungs, where it can be passed through to the blood. The person can still breathe, but it might be hard to breathe, especially if the pneumonia affects both lungs.\n\nPneumonia can happen to people at any age, from tiny babies to really old people. Getting wet doesn't cause pneumonia, but an infection from bacteria or a virus does. A cold or flu that gets worse can turn into pneumonia. That's because the cold or flu will irritate the lungs, creating an environment where it's easier for pneumonia germs to move in and start an infection.
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Lung\nFrom Wikipedia, the free encyclopedia\n\nThe lungs flank the heart and great vessels in the chest cavity. (Source: Gray's Anatomy of the Human Body, 20th ed. 1918.)\n\nThe lungs flank the heart and great vessels in the chest cavity. (Source: Gray's Anatomy of the Human Body, 20th ed. 1918.)\nAir enters and leaves the lungs via a conduit of cartilaginuous passageways — the bronchi and bronchioles. In this image, lung tissue has been dissected away to reveal the bronchioles. (Source: Gray's Anatomy of the Human Body, 20th ed. 1918.)\n\nAir enters and leaves the lungs via a conduit of cartilaginuous passageways — the bronchi and bronchioles. In this image, lung tissue has been dissected away to reveal the bronchioles. (Source: Gray's Anatomy of the Human Body, 20th ed. 1918.)\n\nThe lung is the essential organ of respiration in air-breathing vertebrates. Its principal function is to transport oxygen from the atmosphere into the bloodstream, and to excrete carbon dioxide from the bloodstream into the atmosphere. This it accomplishes with the mosaic of specialized cells that form millions of tiny, exceptionally thin-walled air sacs where gas exchange takes place. Lungs also have nonrespiratory functions.\n\nMedical terms related to the lung often begin with pulmo-, from the Latin pulmonarius ("of the lungs"), cognate with the Greek pleumon ("lung").\n\nRespiratory function\n\nEnergy production from aerobic respiration often requires oxygen and produces carbon dioxide as a by-product, creating a need for an efficient means of oxygen delivery to cells and carbon dioxide excretion from cells. In smaller organisms, such as single-celled bacteria, this process of gas exchange can take place entirely by simple diffusion. In larger organisms, this is not possible; only a small proportion of cells are close enough to the surface for oxygen from the atmosphere to enter them through diffusion. Two major adaptations made it possible for organisms to attain great multicellularity: an efficient circulatory system that conveyed gases to and from the deepest tissues in the body, and a large, internalised respiratory system that centralized the task of obtaining oxygen from the atmosphere and bringing it into the body, whence it could rapidly be distributed to all tissues via the circulatory system.\n\nIn air-breathing vertebrates, respiration occurs in a series of steps. Air is brought into the animal via the airways — in reptiles, birds and mammals this often consists of the nose; the pharynx; the larynx; the trachea; the bronchi and bronchioles; and the terminal branches of the respiratory tree. The lungs of mammals are a rich lattice of alveoli, which provide an enormous surface area for gas exchange. A network of fine capillaries allows transport of blood over the surface of alveoli. Oxygen from the air inside the alveoli diffuses into the bloodstream, and carbon dioxide diffuses from the blood to the alveoli, both across thin alveolar membranes. The drawing and expulsion of air is driven by muscular action; in early tetrapods, air was driven into the lungs by the pharyngeal muscles, whereas in reptiles, birds and mammals a more complicated musculoskeletal system is used. In the mammal, a large muscle, the diaphragm (in addition to the internal intercostal muscles), drive ventilation by periodically altering the intra-thoracic volume and pressure; by increasing volume and thus decreasing pressure, air flows into the airways down a pressure gradient, and by reducing volume and increasing pressure, the reverse occurs. During normal breathing, expiration is passive and no muscles are contracted.. [\n\nNonrespiratory functions\n\nIn addition to respiratory functions such as gas exchange and regulation of hydrogen ion concentration, the lungs also:\n\n    * influence the concentration of biologically active substances and drugs used in medicine in arterial blood\n    * filter out small blood clots fo