The Respiratory System: Functions and Path of Air

1. - The Respiratory System • Complete unit planner by writing activities and homework in the appropriate places. • Read the paragraph on page 564. • Write the answer to the following question as today’s bellringer: Why do astronauts wear space suits and carry oxygen with them when they walk outside a spacecraft?

2. - The Respiratory System Respiratory System Functions • Two important truths about the air you breathe… • 1. The oxygen your body needs comes from the atmosphere – the blanket of gases that surrounds the earth. • 2. When you exhale, most of the air goes back into the atmosphere.

3. - The Respiratory System Respiratory System Functions • 1. The respiratory moves oxygen from the outside environment into the body. • 2. The respiratory also removes carbon dioxide and water from the body.

4. - The Respiratory System Respiratory System Functions • Oxygen from the air and glucose from digested food are both carried to the cells by the blood. During respiration, oxygen reacts with glucose to release energy.

5. - The Respiratory System Respiratory System Functions • So what is needed for the energy-releasing chemical reactions that take place inside your cells? oxygen

6. - The Respiratory System So what is respiration? • Respiration is the process in which oxygen and glucose undergo series of chemical reactions inside cells to release energy. • In addition to energy, carbon dioxide and water are also products of respiration.

7. - The Respiratory System A Little Review Respiratory System Digestive System Circulatory System

8. - The Respiratory System The Path of Air

9. - The Respiratory System Your Nose

10. - The Respiratory System Your Nose Air enters the body through openings in the nose called nostrils and then moves into spaces called the nasal cavities which are lined with cilia and mucus. Cilia are tiny hairlike extensions that sweep mucus into the throat. Mucus moistens the air and traps particles in the air.

11. - The Respiratory System The Path of Air

12. - The Respiratory System Your Throat Another name for the pharynx… The pharynx is shared by both the respiratory system and the digestive system. Both the nose and the mouth connect to the pharynx.

13. - The Respiratory System The Path of Air

14. - The Respiratory System Your Windpipe Another name for the trachea… The trachea feels like a tube with a series of ridges. These ridges are made up of rings of cartilage that strengthen the trachea and keep it open.

15. - The Respiratory System The Path of Air

16. - The Respiratory System The Path of Air

17. - The Respiratory System Gas Exchange • After air enters an alveolus, oxygen passes through the wall of the alveolus and then through the capillary wall into the blood. Carbon dioxide and water pass from the blood into the alveoli.

18. - The Respiratory System How You Breathe • When you breathe, the actions of your rib muscles and diaphragm expand or contract your chest. As a result, air flows in or out.

19. - The Respiratory System Breathing and Speaking • Two vocal cords, folds of connective tissue that produce your voice, stretch across the opening of the larynx. Air moving over the vocal cords causes them to vibrate and produce sound.

20. - The Respiratory System Sequencing • As you read, make a flowchart that shows the path of air in the respiratory system. Write each step of the process in a separate box in the order in which it occurs. Path of Air Air enters the nose. To the pharynx To the trachea To the bronchi To the lungs To the alveoli

21. End of today’s notes.

22. - The Respiratory System Surface Area • Surface area refers to the total area of all the surfaces of a three-dimensional object. Consider a cube, which has six equal sides. Each side measures 2 cm by 2 cm. • 1. To find the surface area of the cube, first calculate the area of one of the six sides: • Area = length X width = 2 cm X 2 cm = 4 cm2 • Each side has an area of 4 cm2. • 2. Then, add the areas of the six sides together: • 4 cm2 + 4 cm2 + 4 cm2 + 4 cm2 + 4 cm2 + 4 cm2 = • 24 cm2 • The surface area of the cube is 24 cm2.

23. Practice Problem Calculate the surface area of a cube whose sidemeasures 3 cm. 54 cm2 - The Respiratory System Surface Area

24. - The Respiratory System Breathing Process Activity • Click the Active Art button to open a browser window and access Active Art about the breathing process.

25. - The Respiratory System The Air You Breathe • The air you breathe in contains several different gases, shown in the circle graph on the left. The air you breathe out contains the same gases, but in the amounts shown in the circle graph on the right.

26. Percent of a gas breathed in or out Reading Graphs: What does each wedge of the graphs represent? - The Respiratory System The Air You Breathe

27. Oxygen; less oxygen is breathed out than breathed in—meaning that some must have been used by the body. Interpreting Data: Based on the data, which gas is used by the body? Explain. - The Respiratory System The Air You Breathe

28. There is a higher percentage of carbon dioxide in exhaled air. Carbon dioxide is a waste product of cellular activity. Drawing Conclusions: Compare the percentage of carbon dioxide in inhaled air with the percentage in exhaled air. How can you account for the difference? - The Respiratory System The Air You Breathe

29. Nitrogen is not used by the body and is not a waste product. Inferring: Explain why the percentage of nitrogen is the same in both inhaled air and exhaled air. - The Respiratory System The Air You Breathe

30. End of Section:The Respiratory System