The Effects of Smoking

1. The Effects of Smoking Describe the effects of smoking on the mammalian gas exchange system, with reference to the symptoms of • chronic bronchitis • emphysema (chronic obstructive pulmonary disease or COPD) • lung cancer

2. Constituents of cigarette smoke that cause damage to health Cigarette smoke contains over 4000 different chemicals. The main problems are caused by : • Tar, a mixture of substances including carcinogens (chemicals that cause cancer) • Nicotine • Carbon Monoxide

3. Short Term Effects of Tar on Gas Exchange System (NB: tar does not pass through lung tissue into blood stream)

4. Short Term Effects of Tar on Gas Exchange System (NB: tar does not pass through lung tissue into blood stream)

5. Long Term Effects of Tar on Gas Exchange System

6. Long Term Effects of Tar on Gas Exchange System

7. Diseases of Gas Exchange system associated with smoking • Lung Cancer • Bronchitis • Emphysema • COPD (chronic obstructive pulmonary disease)

8. Lung Cancer SEM of a lung cancer cell. Cancer cells divide rapidly in a chaotic, uncontrolled manner. They may clump to form tumours, which invade and destroy surrounding tissues. Lung cancer is a common form of cancer, frequently associated with smoking tobacco. It often develops at the entrance to the bronchi It causes a persistent cough, shortness of breath and chest pain. Blood may be coughed up in sputum. Cancer may spread to other areas of the body. Treatment includes surgical excision of the affected areas of the lung, with radiotherapy and chemotherapy.

9. Lung cancer Outside lung Inside lung Black deposits of tar in tissues Large cancerous tumour

10. Lung cancer

11. Signs and Symptoms • Often no symptoms early on • Later symptoms maybe: • cough, shortness of breath, wheezing, chest pain, and coughing up blood

12. Bronchitis

13. BronchitisInflammation of the airway lining, damaged cilia, increased mucous production. Persistent cough, mucus filled with microbes and white blood cells

14. Signs and symptoms of Bronchitis • Cough • Production of mucus (sputum), either clear or white or yellowish-gray or green in color • Shortness of breath, made worse by mild exertion • Wheezing • Fatigue • Slight fever and chills • Chest discomfort • Frequent respiratory infections (such as colds or ‘flu) with a worsening productive cough

15. Emphysema

16. Emphysema Damaged alveoli Normal alveoli

17. Emphysema SEM of human lung tissue affected by emphysema. Emphysema is a disease in which the alveoli of the lung become enlarged and the walls separating them are damaged. This damage occurs as a result of elastase enzyme breaking down the elastic fibres which allow the alveoli to expand and recoil. There is difficulty exhaling. Surface area for gaseous exchange is reduced, restricting oxygen uptake. This may cause breathlessness, bluish skin, and heart or respiratory failure. Occurrence of emphysema is strongly associated with smoking. Treatment of emphysema is with drugs and the cessation of smoking.

18. Emphysema signs and symptoms • Shortness of breath, shallow breathing • Wheezing, difficulty breathing out • Fatigue, extreme tiredness • Heart failure • Cyanosis / blue tinge to skin • High blood pressure to lungs • Enlarged right side of heart

19. Learning Outcome Describe the effects of nicotine and carbon monoxide in tobacco smoke on the cardiovascular system with reference to the course of events leading to • atherosclerosis • coronary heart disease • strokes.

20. Match the effect that CO and nicotine have on the body to the damage that they cause • Sort the cards into 6 pairs

21. Remember Nicotine and Carbon Monoxide enter the lungs and pass through the lung surface into the blood

22. Development of Atheromas (Atherosclerosis) • Damage to the arterial endothelium by CO or hypertension • Cholesterol, fatty deposits and cellular waste are deposited under the damaged area in the wall, which is then repaired • Inflammation at the site stimulates monocytes to infiltrate the area • Monocytes differentiate into macrophages which ingest the cholesterol and turn into “foam cells”. This is what forms the “plaque” • These changes also stimulate smooth muscle cells to multiply and form a “cap” • The whole area increases in size and extends out into the lumen of the artery restricting blood flow. • The atheroma may finally break through the repaired endothelium again and release some of the lumps of fatty deposit into the blood stream. This can increase the likelihood of blockages in small arteries.

23. Development of Atheroma in arterial walls (Atherosclerosis)

24. Reduction of arterial lumen by atheroma lumen atheroma

25. Watch real player video on atherosclerosis

26. Essay Explain how Nicotine and Carbon Monoxide contribute to the occurrence of Coronary Heart Disease and Strokes