Biology

What Is It
The respiratory system comprises of the nose, mouth, throat, larynx, trachea, bronchi and lungs. The primary function of the respiratory system is to supply the blood with oxygen in order for the blood to deliver oxygen to all parts of the body. The respiratory system does this through breathing. Breathing, controlled by the respiratory system, is a continuous process of which a person is normally unaware. If breathing stops, however, a person becomes acutely aware of the fact. An individual can go days without food and water and hours without sleep, but only five or six minutes without air. Anything beyond that would be fatal. The trillions of cells in the body need a constant and generous amount of oxygen to carry out their vital functions. As they use that oxygen, they give off carbon dioxide as a waste product. This exchange of gases is the respiratory systems means of getting oxygen to the blood. Oxygen is required by cells in the body to allow various metabolic reactions to take place and to produce energy and is therefore essential to life. (Respiratory System, n. d.)

What Does It Do
It is the role of the respiration system, working in conjunction with the cardiovascular system, to supply the oxygen and dispose of the carbon dioxide. The breathing process is governed by the actions of the central nervous system, the diaphragm, the lungs, and the circulatory system. There is a respiratory center in the brain which regulates the process of respiration. Muscles in the chest, like the diaphragm and those between the ribs, help in the expansion and collapse of the lungs during each breath. After the exchange of gases in the lungs, oxygenated blood usually enters the circulatory system to reach all parts of the body. (D. Corazon, n.d.)

What Makes Up the Respiratory System
Here are the main components of the Respiratory System (The major components, 2003)
Nose  it moistens, filters, and warms the air on its way to the lungs. It senses or detects odors and it wafts particles away from the lungs.

Larynx  also known as the voice box, it contains vocal cords that vibrate when sound is made. It forms the sounds that comprise speech.

Pharynx  it acts as a passageway for food from the mouth to the esophagus, and as an air passage from the nasal cavity and mouth to the larynx. It also acts as a resonating chamber for the sounds produced in the larynx.

Trachea  the windpipe, it connects the external respiratory organs (nose and mouth) with the lungs.
Bronchi and Bronchioles  Bronchi are air passages beyond the trachea while bronchioles are subdivisions of the bronchial tree. These are components essential for external respiration.

Pleura  the covering of the lungs. The covering consists of serous membrane, which has a smooth shiny moist surface due to the secretion of small amounts of fluid. This fluid lubricates the opposing visceral and parietal surfaces so that they can slide painlessly over each other during breathing.
Alveoli - An alveolus in the lung is a blind-ended air sac of microscopic size. These are also components essential for external respiration.

Diaphragm  it plays an important part in breathing. It contracts with each inspiration, becoming flattened downwards and increasing the volume of the thoracic cavity. With each expiration, the diaphragm relaxes and is restored to its dome shape.

The Nose
The nose is the most prominent feature located in the middle of the face of humans. It is the beginning part of the  HYPERLINK httpwww.buzzle.comarticlesstructure-of-the-human-respiratory-system.html respiratory system that is involved in inhalation. The important functions of the nose are to filter the atmospheric air before passing it further into the respiratory system and to provide the sense of smell. In fact, it acts as an interface between the air of the  HYPERLINK httpwww.buzzle.comarticleshuman-body-systems bodys respiratory passages and the air of the atmosphere. The atmospheric air entering through the nostrils is led to the nasal cavity, which further passes to the pharynx, trachea, bronchi and finally, to the lungs.

The structure of a human nose is composed of bones, cartilage and fibro fatty tissues. The external feature of a nose or the  HYPERLINK httpwww.buzzle.comarticlesdifferent-types-of-noses.html type of nose depends upon the ethmoid bone and the cartilage. The supporting structure of the upper part of nose is mostly made up of bones. The topmost portion near the eye sockets consists of two nasal bones, which is linked to the frontal bone of the forehead. These nasal bones are joined to form the nose bridge. On the sides, they are connected with the lateral process of the maxilla by a tough fibrous membrane. At the base, the nasal bones are connected with septal and lateral nasal cartilage. The lower part of the nose is made up of cartilages. These cartilages give shape to the external feature of the nose. The nose bridge continues with the septal cartilage to form the nasal septum, which separates the nostrils.

The nostrils continue with the nasal cavity. There are three horizontal outgrowths of bones, called turbinate or conchae, which divide the nasal cavity into three groove-like air passages. Conchae increase the surface area of the nasal cavity. The three turbinates are named as inferior, middle and superior turbinates, according to their position and functions. They are important for maintaining the temperature, humidification (up to 98 water saturation) and filtration of the air when it passes. On either side of the septal cartilage, there lies the lateral nasal cartilage. Just below the lateral nasal cartilages, the greater alar cartilage is present, which is a thin, flexible plate that forms the medial and lateral wall of the nostril. In addition to greater alar cartilages, there are three or four small cartilages that are called as lesser alar cartilages. Both the greater and lesser alar cartilages give the overall shape of the nostrils. Hair are present inside the nostrils that help in filtration and humidification as the air from the atmosphere passes them. Hence, nose hair serves as a defense mechanism against the harmful pathogens and solid particulate matter present in the air. Both the nostrils and nasal cavity are lined by mucous membranes along with cilia. The mucous membrane secretes a sticky substance called mucus. The mucus and cilia filter the air and prevent the entry of foreign particles such as microorganisms, dust and particulate matter inside the respiratory system. The mucus also helps in moistening the air. Underneath the mucous membrane, there are blood capillaries that help to warm the air.

Overall, nose is responsible for respiration and for providing the sense of smell. At present, nose surgery or rhinoplasty is performed to improve the appearance of the nose and also to correct different medical problems such as deviated septum, which impairs the respiration process. A deviated septum may be present at birth or may be resulted due to an accident. Today, nose surgery has become an important part of  HYPERLINK httpwww.buzzle.comarticlescosmetic-surgery cosmetic or plastic surgery. (N.  HYPERLINK httpwww.buzzle.comauthors.aspauthor21405 Sandhyarani, n.d.)

What is Asthma
Asthma is a chronic lung disease that inflames and narrows the airways. Asthma causes recurring periods of wheezing, chest tightness, shortness of breath, and coughing. The coughing often occurs at night or early in the morning. Asthma affects people of all ages, but it most often starts in childhood.

The  HYPERLINK httpwww.nhlbi.nih.govhealthdciDiseaseshlwhlw_what.html airways are tubes that carry air into and out of your lungs. People who have asthma have inflamed airways. This makes the airways swollen and very sensitive. They tend to react strongly to certain substances that are breathed in. When the airways react, the muscles around them tighten. This causes the airways to narrow, and less air flows to your lungs. The swelling also can worsen, making the airways even narrower. Cells in the airways may make more mucus than normal. Mucus is a sticky, thick liquid that can further narrow your airways. This chain reaction can result in asthma symptoms. Symptoms can happen each time the airways are irritated.

Sometimes, symptoms are mild and go away on their own or after minimal treatment with an asthma medicine. At other times, symptoms continue to get worse. When symptoms get more intense or additional symptoms appear, this is an asthma attack. Asthma attacks also are called flare-ups or exacerbations.

It is important to treat symptoms when you first notice them. This will help prevent the symptoms from worsening and causing a severe asthma attack. Severe asthma attacks may require emergency care, and they can cause death. Asthma cannot be cured. Even when you feel fine, you still have the disease and it can flare up at any time. But with todays knowledge and treatments, most people who have asthma are able to manage the disease. They have few, if any, symptoms. They can live normal, active lives and sleep through the night without interruption from asthma.