biology4alevel600

9.1    The gas exchange system 9.2    Smoking The gas exchange system is responsible for the uptake of oxygen  into the blood and excreting carbon dioxide. An understanding of this system shows how cells, tissues and organs function  together to exchange these gases between the blood and the environment. The health  of this system and of the cardiovascular system is put at risk by smoking. Learning outcomes Candidates should  be able to: 9.1    The gas exchange system The gas exchange surface in the lungs is extensive, very thin, well supplied with blood and well ventilated. The trachea and bronchi  provide little resistance to the movement of air to and from the alveoli. a)   describe the gross structure of the human gas exchange system b)   observe and draw plan diagrams of the structure of the walls of the trachea, bronchi,  bronchioles and alveoli indicating  the distribution of cartilage,  ciliated epit...

• The gas exchange system • Smoking and smoking-related diseases Learning Outcomes Candidates should be able to: (a) [PA] describe the structure of the human gas exchange system, including the microscopic structure of  the walls of the trachea, bronchioles and alveoli with their associated blood vessels; (b) [PA] describe the distribution of cartilage, ciliated epithelium, goblet cells and smooth muscle in the  trachea, bronchi and bronchioles; (c) describe the functions of cartilage, cilia, goblet cells, mucous glands, smooth muscle and elastic fibres in  the gas exchange system; (d) describe the process of gas exchange between air in the alveoli and the blood; (e) describe the effects of tar and carcinogens in tobacco smoke on the gas exchange system; (f) describe the signs and symptoms that enable diagnosis of lung cancer and chronic obstructive pulmonary disease (COPD) (emphysema and chronic bronchitis); (g) describe the effects of nicotine and carbon monoxide on the ...