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Respiration and Gas Exchange
Quick questions on Effects of exercise and smoking explained: O-Level Biology
8short Q&A pairs drawn directly from our worked dot-point answer. For full context and worked exam questions, read the parent dot-point page.
What is the harmful substances in tobacco smoke?Show answer
Tobacco smoke contains many harmful substances. Three important ones are:
What is diseases linked to smoking?Show answer
Long-term smoking is linked to lung cancer, chronic bronchitis (inflamed, mucus-filled airways), emphysema (destroyed alveoli, reducing surface area for gas exchange), and coronary heart disease.
What is tar?Show answer
A sticky brown substance that collects in the airways and lungs. It is a carcinogen (causes lung cancer), damages the airways (contributing to bronchitis and the destruction of alveoli in emphysema), and paralyses or destroys the cilia that sweep mucus and dirt out of the airways.
What is nicotine?Show answer
An addictive substance that makes smoking hard to give up. It also raises the heart rate and blood pressure and narrows blood vessels.
What is carbon monoxide?Show answer
A gas that binds to haemoglobin in red blood cells in place of oxygen, reducing the amount of oxygen the blood can carry, so the body gets less oxygen.
What is q1?Show answer
State two ways breathing changes during exercise. [2 marks]
What is q2?Show answer
State one harmful effect of carbon monoxide in tobacco smoke. [1 mark]
What is q3?Show answer
Explain why a smoker's airways become blocked with mucus. [2 marks]