National 4 Science

1. National 4 Science Human Health Physiological measurements of the lungs

2. Physiological Measurements of the Lungs • What three physiological measurements are used to determine the health of the lungs? • What is vital capacity? • How is vital capacity measured? • What does it indicate about the lungs?

3. What physiological measurements can be used to determine the health of the lungs? • Three physiological measurements that can be used to indicate the health of the lungs are: • Vital capacity • Tidal volume • Peak flow

4. What is Vital Capacity? • Vital capacity is the maximum volume of air that a person can breathe out after they have taken in as deep a breath as possible

5. What factors affect vital capacity? • The following factors affect vital capacity: • Body size: the larger the person’s build the greater their vital capacity • Age: reaches its max around age 20 • Gender: on average women have a lower vital capacity than men • Fitness: as fitness increases vital capacity increases

6. How is vital capacity measured – low tech? • Take in as deep a breath as possible, breathe out and measure the volume of displaced water

7. How is vital capacity measured – high tech? • Take in a deep breath • Blow into the mouth piece • Take the reading • Match to the index card

8. Questions • Intermediate 1 Biology textbook • p58 – 59 • Questions 4 and 5