IGCSE Biology Paper-3: Specimen Questions with Answers 233 - 234 of 358
Passage
shows part of the human gas exchange system.
Question 233 (3 of 4 Based on Passage)
Write in Short
Short Answer▾Label the structures on Fig. 12. 1 using words from the list:
- bronchiole
diaphragm
larynx
rib
trachea.
Explanation
Question 234 (4 of 4 Based on Passage)
Explanation
Damaging Components of Tobacco Smoke Include
- Tar: is the word for the solid particles suspended in tobacco smoke. The particles contain chemicals, including cancer-causing substances (carcinogens) . Tar is sticky and brown, and stains teeth, fingernails, and lung tissue
carbon monoxide: is a poisonous gas. It is odorless and colorless and, in large doses, quickly causes death because it takes the place of oxygen in the blood. In people who smoke, the carbon monoxide in their blood makes it harder for oxygen to get to their organs and muscles
oxidizing chemicals: are highly reactive chemicals that can damage the heart muscles and blood vessels of people who smoke. They react with cholesterol, leading to the build-up of fatty material on artery walls. Their actions lead to heart disease, stroke, and blood vessel disease
metals: tobacco smoke contains several metals that cause cancer, including arsenic, beryllium, cadmium, chromium, cobalt, lead, and nickel
radioactive compounds: tobacco smoke contains radioactive compounds that are known to be carcinogenic.