Respiration mainly consists of two processes. Respiration Internal or cellular respiration is the process by which glucose or other small molecules are oxidized to produce energy: this requires oxygen and generates carbon. dioxide. External respiration (breathing) simply involves the step of taking oxygen from the air and returning carbon dioxide to it. “Anatomy and functions of the respiratory system and its components” The respiratory tract, where external respiration occurs, begins with the nose and mouth. The windpipe (trachea) extends from the neck to the thorax, where it divides into the right and left main bronchi, which enter the right and left lungs, dividing into smaller bronchi and bronchioles and ending in small sacs aerial or alveoli. , where gas exchanges take place. The lungs are divided first into right and left, the left being smaller to accommodate the heart, then into lobes (three on the right, two on the left) supplied by the lobar bronchi. The bronchi, pulmonary arteries and veins (which supply deoxygenated blood and remove oxygenated blood), bronchial arteries and veins (which supply oxygenated blood to the substance of the lung itself), and lymphatics all enter and exit the lung through its root (or hilum). Lymph nodes blackened by soot particles can often be seen here and the substance of the lungs itself may be blackened by soot in city dwellers or heavy smokers. Each lobe of the lung is then divided into pyramidal bronchopulmonary segments. The bronchopulmonary segments have the apex of the pyramid in the hilum from where they receive a tertiary bronchus and appropriate blood vessels. Gas exchange is based on simple diffusion. In order to provide enough oxygen and get rid of enough car...... middle of paper ...... that a doctor can perform when diagnosing asthma, including: Chest x-rays Tests of skin allergy Total serum IGE levels Nasal examinations Diagnosis in infants: Doctors depend on the parents' ability to be observant and take notes. However, research has shown that immediately starting asthma medications and treating wheezing can help with the diagnosis and, at the same time, help the child. References Asthma' introductory material taken from the book: 'Current Medical Diagnosis and Treatment, Ed 37, Pg: 256-257 Some diagnostic procedures adapted from the 'Diagnosis of Asthma' website accessed 05/20/2003 www.clearbreathing .com/ Disease/asthma_diagnosis.asp Respiratory system material collected from: Introductory Anatomy: Respiratory System Dr DRJohnson, Center for Human Biology, retrieved 05/20/2003 from: http://www.leeds.ac.uk /chb/readings/anatomy7.html