The Respiratory System

1. The Respiratory System

3. LUNG CAKE

4. Functions of the Respiratory System • Obtain O2from environment • Expel CO2 into the environment • Filter foreign particle out of incoming air • Regulates H2O content and temperature of incoming air • Creates vocal sounds • Contributes to sense of smell • Helps regulate blood pH

5. Steps for Respiration • 1) Breathing or ventilation • Moving air in and out of lungs • 2) External respiration • Exchange of gases between lungs and blood vessels • 3) Transport of gases to cells • 4) Internal respiration • Exchange of gases between blood vessels and cells • 5) Cellular respiration • Using O2 in metabolic processes to create energy

7. Divisions of Respiratory Tract • Upper respiratory tract • Nose • Nasal cavity • Paranasal sinuses • Pharynx • Lower respiratory tract • Larynx • Trachea • Bronchial tree • Lungs

9. Nose • Bone and cartilage • Support structure • Nostrils • Openings for entry of air • Nose hairs • Guard entrance and protect against particles

11. Nasal Cavity • Hollow space behind nose • Nasal septum • Bone and cartilage structure dividing cavity into 2 sides • Nasal conchae • Projections from nasal cavity wall; increase surface area • Lining of nasal cavity • Pseudostratifiedepithelial cells with mucous-secreting goblet cells • Particles are trapped and moved out and air is warmed and moistened

12. The NOSE bones and cartilage support nose, two openings (nostrils), hair filters large particles Nasal Cavity – hollow space behind the nose  Nasal septum – divides the nose (bone)

13. 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

14. Function of the conchae - increase surface area Mucus Membrane - warms and moistens air, also traps particles (dust)     *particles go to          stomach Nasal Conchae

15. Paranasal Sinuses • Air-filled sacs within skull bones • Reduce the weight of the skull • Affect sound of the voice

16. Paranasal Sinuses - – spaces within the  bones • maxillary • frontal • ethmoid • sphenoid  reduce the weight of skull and are resonant chambers for voice.

19. Pharynx • Shared with digestive system • Divisions: • Nasopharynx • Oropharynx • Larygopharynx • Otherwise known as hypopharynx • Openings: • Oral cavity • Nasal cavity • Esophagus • Trachea

20. The three pharyngeal regions Pharynx – behind the oral cavity, between the nasal cavity and larynx (space, not a structure)

23. Larynx • Enlargement at beginning of trachea • Framework of muscle and cartilage bound by elastic tissue • Largest cartilages: • Thyroid (Adam’s apple) • Cricoid • Epiglottic

25. Vocal Cords • Housed in larynx • False vocal cords • Fold of tissue that helps to close passageway when swallowing • True vocal cords • Vibrate when air is forced through causing sound • Tension of chords helps regulate pitch • Force of air helps regulate volume of sound

26. Larynx – enlargement at the top of the trachea and below pharynx, conducts air in and out of trachea, houses vocal cords - composed of a framework of muscles and cartilages (thyroid (Adam’s apple), cricoids, epiglottic cartilages)

27. Glottis • Triangular opening between vocal cords • When swallowing: • False vocal cords close glottis • Larynx raises and presses epiglottis against opening

28. Glottis - 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)

29. www.voiceinfo.org Steven Tyler's Vocal Cords

31. Glottis – triangular slit that opens during breathing/talking, and closes during swallowing Epiglottis – flaplike structure that stands upright, allows air to enter larynx, during swallowing it presses downward and prevents food from entering air passages

32. LARYNGITIS When the mucus membrane becomes swollen and prevents the vocal cords from vibrating freely. Trachea (windpipe), flexible cylinder with cartilage to give it stiffness and keep it from collapsing    Trachea leads to the BRONCHIAL TREE

33. Trachea • Also called windpipe • Descends anterior to esophagus • Lining of trachea: • Pseudostratifiedepithelial cells with mucous-secreting goblet cells • Enclosed with C-shaped rings of hyaline cartilage to prevent tube from collapsing

34. Bronchial Tree • Branching tubes connecting trachea to site of gas exchange in lungs • Right and left primary bronchi  Secondary bronchi  Tertiary bronchi  Bronchioles  Terminal bronchioles  Respiratory bronchioles  Alveolar ducts  Alveolar sacs  Alveoli • Amount of cartilage decreases through tract • Amount of smooth muscle in the walls increases through tract

35. Primary bronchii --> bronchioles --> alveolar ducts -->  sacs                                                                         -->  alveoli                                                                       *gas exchange

37. Alveoli • Terminal sacs at the end of the tract • Surrounded by network of blood capillaries • Site of gas exchange • Respiratory membrane: • Simple squamous epithelium in alveoli and blood capillary • Basement membrane fuses the two (alveoli and capillary) together

38. Alveoli & Lungs

39. ALVEOLI

41. $20,000 PYRAMID! • A word/phrase will be posted – person A (who is facing the board) must attempt to explain the word (without saying it!) while Person B (who is NOT facing board) will guess what the word is. • NO DRAWING! • If your partner gets them all right – with NO CHEATING – raise your hands! • GET READY!!!! • Alveoli • Larynx • Trachae

42. Quick Quiz 1.  What do you call the bones found within the nasal cavity? 2.  What specific bone divides the nasal cavity into two sides? 3.   The space at the back of the mouth is the________. 4.  The spaces within the bones of the skull are called the ______________________ 5. What structure is known as the windpipe? ______ 6.  What is the triangular slit that opens during breathing and talking? 7. In what structures does gas exchange occur? 8. During swallowing, this flap closes to prevent food from entering the airway: ______________________

43. Lungs • Located in thoracic cavity: • Mediastinum between • Thoracic cage surrounds • Diaphragm below • Suspended by bronchi and blood vessels • Cover by visceral pleura which folds back to become parietal pleura • Potential space between is pleural cavity • Small layer of serous fluid between • Right lung: 3 lobes • Left lung: 2 lobes

44. LUNGS - spongy tissue that sit within the pleural cavity

45. Right Lung          = 3 lobes Left Lung           = 2 lobes Serous fluid lubricates lungs during breathing

47. EXHALATION As the diaphragm and other muscles relax, ELASTIC RECOIL from surface tension forces air out.   Muscles can force extra air out or in

48. Inspiration • At rest, pressure of air and thoracic cavity are the same; • NO net movement of air • Pressure must be decreased in thoracic cavity for air to move in • Diaphragm is contracted (lowered) and external (inspiratory) intercostal muscles contract as well • Contractions increase cavity volume which decreases pressure

49. Inspiration (cont) • Muscle movements pull on the pleural membranes to expand the lung • Surface tension • Difficulty in expanding alveoli because the walls tend to stick together • Surfactanthelps combat surface tension • Deeper breaths can be taken by contracting muscle more forcefully or by involving other muscles

50. Expiration • Normally passive process • Contracting muscles relax • Elastic recoil and surface tension cause tissue to return to previous state before inspiration • Pressure increases in cavity and forces air out of lungs