1. Respiratory System Chapter 16

2. Functions 1.Obtain O 2 and remove CO 2 2.Filter and trap incoming particles 3.Control temperature and water content of incoming air. 4.Produce vocal sounds 5.Help to regulate blood pH

3. Structures Nose, nasal cavity and sinuses Pharynx Larynx Trachea Bronchial tree Lungs

4. Nose, Nasal Cavity and Sinuses Hairs filter air Mucus Membranes moisten air Capillaries warm air Nasal sinuses affect vocal sound and reduce weight of skull

5. Nasal conchae – bones that divide the nasal cavity, support the mucus membrane and increase surface area (superior, middle, inferior) * deviated septum – when the septum bends to one side

8. Larynx Contains vocal cords Vibration of cords makes sound. Glottis is slit-like opening between vocal cords. Epiglottis is flap to cover windpipe when swallowing food. Adam’s apple – thyroid cartilage Laryngitis : Inflammation/swelling of the vocal cords; caused by infection or irritation of mucous membranes

9. - false vocal folds (do not produce sound) – help close airway during swallowing - true vocal folds (produce sound) – changing shape of the pharynx, and oral cavity changes sounds into words - contracting and relaxing muscles changes pitch (increased tension = higher pitch)

10. Trachea Cartilage C-rings give support. Ciliated mucous (pseudostratified epithelial) tissue filters air Endotracheal Tube : tube inserted into trachea to restore air passageway (video)video Tracheotomy : surgical opening of trachea

11. Bronchial Tree Branched airways leading from trachea to alveolar sacs. Divisions of tree: - Bronchi (1, 2, 3) - Bronchioles - Alveolar sacs Disorders: 1.Asthma – muscular constriction of airways 2.Bronchitis – inflammation of mucosal lining

12. Lungs Soft, spongy organs 3 right lobes, 2 left lobes Visceral pleura and parietal pleura line surface of lungs creating potential space = pleural cavity. Pleural cavity contains serous fluid to reduce friction between layers.

14. Pneumothorax – air enters pleural cavity collapsing lung

15. Alveoli Site of gas exchange Increases surface area Respiratory membrane consists of 3 layers: A – alveolar membrane B – basement membrane C – capillary membrane Surfactant – substance released from epithelium to reduce surface tension (cohesive forces between water molecules) inside open air sacs.

17. Lung disorders: cancer and emphysema

18. Mechanics of Breathing Air flows into and out of the lungs due to a pressure gradient, between the atmospheric pressure and the pressure inside the lungs. Air moves from high to low pressure

19. Normal, quiet exhalation = Elastic recoil of tissues (lungs and muscles). Forceful exhalation = internal intercostal muscles and abdominal muscles. Animation!

20. Forceful inspiration: Muscles such as the external intercostals, pectoralis and sternocleidomastoid can further increase the internal lung space. Normal inspiration : due to pressure difference when thoracic cavity increases from diaphragm and intercostal muscle contractions.

21. NON RESPIRATORY MOVEMENTS Coughing, sneezing, laughing, crying Hiccup - spasm of the diaphragm Yawn - possibly causes by low oxygen levels

22. How much can we breathe in or out in one breath? Measuring Lung Volume… Average pair of human lungs can hold 6 Liters of air.

23. 1.Why do Pulmonary Function Tests need to be performed? * Measures lung function and can assess conditions like asthma, pulmonary fibrosis, cystic fibrosis, & COPD. 2. How is lung volume measured? * Using a SPIROMETER

24. Lung Capacities During normal breathing (at rest), approx. 500ml of air is exchanged = TIDAL VOLUME (TV) Maximum forced inhalation amount = INSPIRATORY RESERVE VOLUME (IRV) Maximum forced exhalation = EXPIRATORY RESERVE VOLUME (ERV) Air that never leaves lungs = RESIDUAL VOLUME (RV) *keeps alveoli open, approx. 1200mL) The passageways that retain air that never reaches alveoli = Anatomic Dead space (approximately 150ml) Maximum exhalation after maximum inhalation = VITAL CAPACITY (VC)

26. What factors can attribute to a large lung capacity? * Your lungs don’t increase in tissue or size after adulthood, it is lung ability and cardiovascular fitness that makes the difference. Gender: males have larger lungs on average Athletes: endurance increases Height: taller people have larger organs Hobbies: wind instruments Habits: non-smokers Environment: people living at high altitudes atm Age: younger vs. older Health: sicknesses decrease VC

27. Breathing Physiology

28. Regulation and Control 2 regions control involuntary breathing: medulla and pons –R–Rhythmicity –D–Depth of breath Voluntary breathing controlled by Cerebral Cortex Problems: Apnea and SIDS - disruption of normal respiratory reflex pattern

29. What is sleep apnea? Pause or slowing of breathing during sleep Video on Sleep Apnea

30. Factors that Affect Breathing Chemical changes – carbon dioxide and H + ions (exercise, holding your breath) Inflation reflex – stretching of lung tissue Emotions: upset, fear, and pain, hyperventilation Surfactant amounts Airway resistance

31. Gas Exchange at the Alveoli Gases move by diffusion. Each gas has its own partial pressure.

32. Other chemicals can cross the respiratory membrane for Breath Analysis. ex: alcohol and diabetes (acetone)

33. Factors that Affect Gas Diffusion Surface area Distance across membranes Change in partial pressure ***Diseases can affect all factors above! 1. pneumonia – increase distance 2. emphysema – decrease surface area

34. Oxygen Transport Most oxygen combines with iron in hemoglobin to form OXYHEMOGLOBIN. Unstable bonds so diffusion is easy.

35. More oxygen is released if: 1. Carbon dioxide increases in blood. 2. Blood pH decreases 3. Blood temperature rises **all this happens during exercise!

37. Hypoxia occurs – deficiency of oxygen reaching tissues leading to cyanosis. –Causes: cardiac arrest, severe head trauma, suffocation, strangulation, and choking, as well as any instance in which oxygen supply is deprived from the body. Carbon Monoxide poisoning – RBC’s have a greater attraction to carry CO instead of oxygen. If not enough oxygen is being taken in…

38. Carbon Dioxide transport 3 Methods of Transport: 1. Dissolved into plasma 2. Form CARBAMINOHEMOGLOBIN - binds with hemoglobin 3. Forms a BICARBONATE ION a. CO 2 reacts with H 2 O to form carbonic acid. (H 2 CO 3 ) - Enzyme carbonic anhydrase speeds up reaction. b. H 2 CO 3 releases H+ to make HCO 3 - (bicarbonate ion) which will travel in plasma to lungs. c. Reaction is reversed when at the lungs.

40. ILLNESSES RELATED TO THE RESPIRATORY SYSTEM 1. Cystic Fibrosis (genetic) 2. Asthma 3. Bronchitis 4. Apnea 5. Emphysema 6. Lung Cancer 7. Altitude Sickness 8. Chronic Obstructive Pulmonary Disease (COPD) 9. Sinusitis 10. Bacterial or Viral Infections (cold, flu, pneumonia)

41. ALTITUDE SICKNESS Acute mountain sickness is brought on by the combination of reduced air pressure and lower oxygen concentration that occur at high altitudes. Symptoms can range from mild to life-threatening, and can affect the nervous system, lungs, muscles, and heart. HAPE – High Altitude Pulmonary Edema is an abnormal build up of fluid in the air sacs of the lungs, which leads to shortness of breath.