A Level Biology Practice Exam

What measurement technique is essential for lung capacity analysis?

1. Cardiography

2. Spirometry

3. Blood gas analysis

4. Endoscopy

The correct answer is: Spirometry

Spirometry is the essential technique for lung capacity analysis because it specifically measures the volume of air that can be inhaled and exhaled by the lungs. This is crucial for determining lung function and diagnosing respiratory conditions. During a spirometry test, a person breathes into a device called a spirometer, which records various parameters, such as tidal volume, vital capacity, and forced expiratory volume. These measurements provide valuable insights into how well the lungs are working and can indicate abnormalities in lung function. In contrast, cardiography is focused on measuring the electrical activity of the heart rather than lung capacity. Blood gas analysis evaluates the levels of gases like oxygen and carbon dioxide in the blood, which is important for assessing respiratory and metabolic function but does not provide direct measurements of lung capacity. Endoscopy involves the use of a flexible tube to visually examine internal body structures, typically for diagnostic purposes, and is not used to measure lung volumes. Thus, spirometry is the only technique directly related to assessing lung capacity.