1. Warm-Up
Name the organs forming the respiratory passageway from the nasal cavity to the alveoli of the lungs.
Explain how the respiratory muscles cause volume changes that lead to breathing.
Sally has a vital lung capacity of 3900 ml. Her tidal volume is 400 ml. Her expiratory reserve volume is 1000 ml. What is her inspiratory reserve volume?

2. Respiratory System
Chapter 16

3. Respiratory System
Respiration: exchanging gases between atmosphere and body cells
Function: supply O2 to the blood and remove CO2

4. Respiratory System Pulmonary Ventilation
Movement of air in & out of the lungs
4 stages :
1. External respiration
Gas exchange between blood & air
2. Gas transport in blood between lungs and body cells
3. Internal respiration
Gas exchange between blood & body cells
4. Cellular respiration
Utilization of the oxygen by mitochondria

5. Respiratory Tract Upper Lower Nose Nasal Cavity Paranasal Sinuses
Pharynx
Lower
Larynx
Trachea
Bronchial Tree
Lungs

8. Anatomy Nose/mouth: filtered, warmed, humidified
Mucus traps bacteria & foreign debris
Cilia sweep mucus toward throat  digested by stomach
Pharynx: throat (passage for food/air)
Tonsils: clusters of lymphatic tissue
Larynx: contains vocal cords
Epiglottis: covers larynx when liquids/food swallowed
Trachea: windpipe; lined with cartilage (C-shaped)
Bronchi: branches to lungs
Bronchioles: smaller branches
Lungs  Alveoli: air sacs for gas exchange

9. Nose Internal support Consists of bone and cartilage Nostrils
Openings through which air can enter and leave
Internal hairs
Filter air entering

10. Nasal Cavity Hollow space behind the nose Nasal septum Nasal conchae
Made of bone and cartilage
Divides cavity into right and left portions
Nasal conchae
Bones that divide the cavity into passageways
Lined with mucous membrane

11. Nasal Cavity Mucous Membrane
Many blood vessels (warm and vaporize air)
Sticky mucus to filter air
Cilia
Move mucus and trapped particles to pharynx to be swallowed
Why is mouth breathing a problem? Why would someone breathe through their mouth?

12. Paranasal Sinuses Air filled spaces within the:
Maxillary, ethmoid, sphenoid, and frontal bones
Lined with mucous membranes
Reduce weight of skull
Provides resonance for voice
Sinus infection
Blockage from infection or allergic reaction

13. Pharynx Throat Passageway for: Helps produce sounds of speech
Air to trachea
Food to esophagus
Helps produce sounds of speech
Sub-divisions:
Nasopharynx, oropharynx, laryngopharynx

14. Larynx Laryngitis Enlargement in the trachea
Made up of cartilages (hyaline)
Thyroid, cricoid, epiglottic
Houses vocal cords
false (upper) & true (lower)
Glottis
Slit between vocal cords
Epiglottis
Made of elastic cartilage
Covers trachea during swallowing
Laryngitis

15. Laryngitis Inflammation of the vocal cords Due to:
Virus, bacteria, overuse

18. Trachea In front of the esophagus Many goblet cells and cilia
Tracheal wall
Not collapsible
Made of 20 incomplete hyaline cartilage rings on the anterior wall of the trachea
No cartilage posterior
Allow for bolus to travel down esophagus

21. Bronchial Tree
Branched airways from the trachea to the air sacs in the lungs
Pathway:
Right and left primary bronchi  bronchioles  alveolar ducts  alveolar sacs  alveoli
Alveoli
Small microscopic air sacs that exchange gas

23. Bronchitis Inflammation of the bronchi
Generally follows a viral respiratory infection
Symptoms include: coughing, shortness of breath, wheezing and fatigue

25. Lungs Soft and spongy Right lung is larger (3 lobes)
Bronchus and vessels suspend the lung
Visceral pleura
Layer of serous membrane folds back to form parietal pleura
Attached to each lung
Parietal pleura
Lines thoracic cavity
Pleural cavity
Space between visceral and parietal pleura filled with serous fluid for lubrication

26. Pneumonia Inflammation of the lung
Most often caused by infection with bacteria, viruses, or other organisms

28. Mechanics of breathing
Inspiration: air flowing into lungs
Atmospheric pressure - force that pushes air into lungs
Surface tension - difficult to inflate alveoli and may cause them to collapse
Surfactant - lipid that prevents alveoli from collapsing
Respiratory distress syndrome
Surfactant not produced until 36 weeks gestation
Treatment: ventilator and artificial surfactant
Expiration: air leaving lungs
Exhaling – removing air from alveoli
Forces:
Elastic recoil of tissues & surface tension
Pneumothorax – collapsed lung

29. Mechanics of Breathing
Muscles:
Diaphragm: dome-shaped muscle separating thoracic and abdominal cavities
External intercostals: pulls ribs to elevate rib cage  inspiratory muscles
Internal intercostals: depresses rib cage

30. Inspiration Expiration
Diaphragm contracts & flattens
External intercostals lifts rib cage
Lungs stretched to larger size
Air pressure inside lungs decrease
Air sucked into lungs
Inspiratory muscles relax
Rib cage descends, lungs recoil
Gases forced out

31. Inspiration vs. expiration

32. Nonrespiratory Movements
Coughing
Force air upward against closure
Clears lower respiratory passages
Sneeze
Clears upper respiratory passages
Laughing
Releasing breath in short expirations

33. Nonrespiratory Movements
Crying
Similar to laughing
Hiccup
Sudden inspiration
Spasmodic contraction of the diaphragm while glottis is closed
Yawning
Aid in respiration by causing a deep breath

34. Interesting Yawning Facts
The average yawn lasts about 6 seconds.
Your heart rate can rise as much as 30% during a yawn.
55% of people will yawn within five minutes of seeing someone else yawn.
Blind people yawn more after hearing an audio tape of people yawning.
Reading about yawning will make you yawn.
Olympic athletes often yawn before competition.

35. Respiratory capacity
Factors that affect Total Lung Capacity: size, age, sex, physical condition

36. Dead Space Volume VC = TV + IRV + ERV
Respiratory Cycle: one inspiration and one exhalation
Vital Capacity (VC): total exchangeable air
VC = TV + IRV + ERV
Tidal Volume (TV)/Respiratory Volume: amount of air in/out during normal breath (~500ml)
Inspiratory Reserve Volume (IRV): forced in air over tidal volume (~3100)
Expiratory Reserve Volume (ERV): air forcibly exhaled (~1200)
Residual Volume (RV): air still left in lungs after exhale (~1200)
allows gas exchange to continue between breaths
Dead Space Volume
Air in respiratory passages that does NOT contribute to gas exchange

37. spirometer
Used to measure respiratory capacities

38. Control of Respiration
Control center = medulla oblongata
Controls basic breathing rhythm
Pons:
Control breathing rate
Responds to pH changes in blood
High CO2  carbonic acid forms  lowers pH
O2 sensors in the aorta and carotid arteries

39. Factors Affecting Breathing
Low blood oxygen has little direct effect
Emotionally upset
Increased CO2 is the stimulus
Hyperventilation
Voluntary, rapid and deep breathing
Lowers blood CO2 levels
Allows breath to be held for longer periods of time (scuba divers)

40. Gas transport in blood
Oxygen: attaches to hemoglobin molecules inside RBC’s
Factors that release O2 from hemoglobin
Carbon dioxide increases
pH lowers
Temperature increases
Hypoxia
Deficiency of O2 reaching the tissues
Decreased bp, anemia, inadequate blood flow, defect at cellular level (cyanide poisoning)
Hemoglobin: respiratory pigment, contains 4 heme groups with iron (Fe)
Oxyhemoglobin

41. Gas transport in blood Carbon dioxide: Dissolved in plasma (7%)
Transported as bicarbonate ions (70%)
Bound to hemoglobin (23%)
Forming carbaminohemoglobin
In HIGH concentrations can convert to carbonic acid

42. Respiratory Disorders

43. chronic obstructive pulmonary disease (COPD)
Group of lung diseases  blocks airflow and makes breathing difficult
Emphysema (lose elasticity of lung tissue) & chronic bronchitis (excess mucus)
Features:
History of smoking
Labored breathing (wheezing, shortness of breath)
Coughing & frequent pulmonary infections
Hypoxic (inadequate O2 delivery – bluish skin)

45. emphysema

46. Lung cancer Uncontrolled growth of abnormal cells in lungs
#1 cause of cancer deaths
Leading cause = SMOKING
Low survival rate (average 9 months after diagnosis)
Contributes to atherosclerosis, heart disease
Treatment: remove diseased lobes, radiation, chemotherapy

48. Respiratory Disorders
Asthma: inflamed, hypersensitive bronchial passages that respond to irritants
Bronchitis: bronchi swollen and clogged
Pneumonia: inflammation of lung caused by infection
Tuberculosis (TB): infectious disease caused by M. tuberculosis bacterium