Transcript File
GCSE LEVEL PE Lesson 11 A healthy active lifestyle and your respiratory system Respiratory System – 1 How the respiratory system works CONNECTOR How many breathes do you take per minute? Average human takes 21 breaths? What happens as a result of exercise? Can you explain why? KEY WORDS Respiratory System Tidal Volume Vital Capacity Oxygen Debt Alveoli Gas Exchange BIG PICTURE You will use your prior knowledge from PE and science to learn about the structure and function of the respiratory system. You will learn about the process of gas exchange and why it is important in exercise through student, teacher and input from powerpoint and text book. LEARNING OUTCOMES All students will have an understanding of the structure and how the respiratory system works. All students will be able to explain what happens during gaseous exchange. Most will be able to explain where gaseous exchange takes place and why it is important in exercise. THE RESPIRATORY SYSTEM KEY QUESTIONS? 1. 2. 3. What do you know about the respiratory system and what it does? Do all athletes breathe as heavily after an event or training session? Why do you think athletes in events such as the 400m are gasping for breath when they finish? Michael Johnson http://www.youtube.com/watch?v=v2W_T77vwfQ 4. 5. Kelly Holmes http://www.youtube.com/watch?v=aV6LfdD97fY Have you ever felt breathless after exercise? What were you doing? WHICH GASES MAKE UP THE AIR WE BREATH IN AND OUT? Inspired Air Expired Air 20% 16% 0.04% 4% Nitrogen 79% 79% Other Gases 1% 1% Oxygen Carbon Dioxide 1. Can you explain why there is a difference in gases between inspired and expired air? 2. Why would expired air resuscitation (EAR) work on a casualty who was not breathing? WHAT HAPPENS TO THE AIR WE BREATH IN? The route of air into the lungs... 1. Air passes through the nose and mouth and then onto the pharynx, larynx and trachea. 2. The trachea splits into two tubes called bronchi (each one is a bronchus) – one going to each lung. 3. The bronchi split into progressively smaller tubes called bronchioles. 4. The bronchioles finally end at small bags called alveoli (each one is an alveolus) where the gas exchange takes place. HOW IS OXYGEN ABSORBED? HTTP://WWW.YOUTUBE.COM/WATCH?V=HIT621PRRO0&FEATURE=RELATED Each bronchus divides into bronchioles and then into tiny air sacs called alveoli The alveoli are covered by capillaries Here oxygen is exchanged into the blood and carbon dioxide taken out of the blood SO WHAT IS THE MAIN FUNCTION OF THE RESPIRATORY SYSTEM? Takes in oxygen Removes carbon dioxide How? Where does CO2 come from? Write a paragraph to describe gaseous exchange in your own words? THE MAIN FUNCTION OF THE RESPIRATORY SYSTEM IS? GASEOUS EXCHANGE THE MECHANISMS OF BREATHING (INSPIRATION AND EXPIRATION) Inspiration is when we breathe in Expiration is when we breathe out The lungs are situated in a flexible sealed space called the thorax At the bottom of the thorax is the diaphragm As the chest expands the diaphragm contracts and pulls down creating a vacuum which allows air to enter When the diaphragm relaxes the lungs contract and air is forced out Breathing is both voluntary and involuntary, what does this mean?. THE MECHANISMS OF BREATHING (INSPIRATION AND EXPIRATION) Take a deep breath... What happens? Inspiration 1. Intercostals and the diaphragm contract to make the chest cavity larger 2. Air is pushed into the lungs by the air pressure outside Expiration 1. The intercostals and the diaphragm relax to make the chest cavity smaller 2. The lungs are squeezed and air is force out DO ALL ATHLETES BREATHE AS HEAVILY AFTER AN EVENT OR TRAINING SESSION? The fitter the athlete the more efficient the respiratory system will work. Allowing Therefore More oxygen to reach the blood.... More blood to reach the muscles.... Why is this important? 1. 2. Oxygen is needed to keep the muscles working. Carbon dioxide needs to be removed. TIDAL VOLUME AND VITAL CAPACITY Two measurements which are used to estimate the efficiency of the respiratory system. Definitions Tidal volume – is the amount of air inspired and expired with each normal breath at resting or during exercise. Vital capacity – is the greatest amount of air that can be made to pass into and out of the lungs by the most forceful inspiration and expiration. (Usually 4 – 5 litres). REVIEW Answer the following questions; 1. What do you know about the respiratory system and what it does? 2. Do all athletes breathe as heavily after an event or training session? 3. Explain why gas exchange is important to an athlete?