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BIOL1191 > Chapter 23 - Respiratory System > Flashcards

Chapter 23 - Respiratory System Flashcards

1
Q

4 Components of Respiration

A
  1. Air movement into & out of lungs
  2. Gas exchange: air to & from blood
  3. Gas transport in blood
  4. Gas exchange: blood to & from tissues
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2
Q

Otorhinolaryngology

A

Study of the diseases of the nose ears, + throat

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3
Q

Pulmonology

A

Study of the diseases of the lungs

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4
Q

Nose

A
  • Most anterior part is cartilage
  • Lined inside w/ mucous membrane
  • 2 nostrils (AKA “external nares/anterior nares”) = openings into each half of nasal cavity from outside
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5
Q

Nasal Cavity

A
  • Internal nares (AKA “posterior nares/choanae”) connect each half of nasal cavity into nasopharynx
  • Nasal cavity partitioned into right & left half by nasal septum (anterior part = “vestibule”)
  • Olfactory receptors in mucosae of inferior surface of cribiform plate and upper surfaces of superior nasal conchae (“Olfactory epithelium”)
  • Nasolacrimal (tear) ducts open into each half of nasal cavity
  • Hard palate separates oral & nasal cavities
  • Soft palate separates nasopharynx from rest of pharynx
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6
Q

Nasal Conchae (AKA “Turbinates”)

A
  • Bony projections which increase surface area
  • Covered by mucous membrane (pseudostratified ciliated columnar epithelium)
  • Functions: filters, warms & humidifies air
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7
Q

Paranasal Sinuses

A
  • Air-filled spaces in maxillary, frontal, ethmoid & sphenoid bones
  • Mucous membrane lined
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8
Q

Sinusitis

A

Inflammation of mucous membrane of paranasal sinuses

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9
Q

Path of Incoming Air

A

External nares -> Vestibule -> Superior, middle & inferior meatuses -> Internal nares -> Nasopharynx

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10
Q

Rhinoplasty

A

Surgical re-shaping of the nose

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11
Q

3 Functions of the Nose

A
  1. Warm, moisten & filter air
  2. Olfaction
  3. Speech (Structures aid in vocal resonance)
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12
Q

Pharynx

A
  • Muscular tube lined by mucous membrane connecting nasal & oral cavities to larynx & pharynx
  • Has 3 subdivisions
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13
Q

3 Subdivisions of the Pharynx

A
  1. Nasopharynx
  2. Oropharynx
  3. Laryngopharynx
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14
Q

Nasopharynx

A
  • Connects throat to nasal cavity via internal nares
  • Site of openings to auditory (Eustachian) tubes
  • Contains pharyngeal tonsil (AKA “Adenoid”)
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15
Q

Oropharynx

A
  • Middle portion of pharynx
  • Communicates w/ oral cavity via the fauces
  • Contains palatine tonsils in anterior lateral wall & lingual tonsils at base of tongue
  • Tonsils = Part of immune system
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16
Q

Laryngopharynx

A
  • AKA “Hypopharynx”
  • Space between epiglottis/hyoid & mouth of esophagus
  • Connects to larynx & esophagus
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17
Q

4 Functions of the Pharynx

A
  1. Common passage for air & food/drink
  2. Routes these substances to either larynx/trachea or esophagus
  3. Immune functions
  4. Vocal resonance
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18
Q

Larynx

A
  • AKA “Voicebox”

- Passageway connecting pharynx to trachea

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19
Q

Thyroid Cartilage

A
  • Apex of the larynx
  • AKA “Adam’s apple”
  • Located at anterior neck
  • Contains thyrohyoid membrane (a broad, fibro-elastic sheet of the larynx; attached below to the upper border of the thyroid cartilage)
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20
Q

3 Unpaired Cartilages in Larynx

A
  1. Thyroid Cartilage
  2. Epiglottis
  3. Cricoid Cartilage
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21
Q

Epiglottis

A
  • Covers glottal opening of larynx during swallowing

- Glottis = true vocal cords (AKA “Vocal folds”) + rima glottidis

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22
Q

Cricoid Cartilage

A

Connects larynx to trachea via cricotracheal ligament

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23
Q

Tracheotomy

A

Incision of cricotracheal ligament

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24
Q

3 Paired Cartilages of the Larynx

A
  1. 2 Arytenoid Cartilages (Sites of attachment of true vocal cords & intrinsic laryngeal muscles)
  2. 2 Corniculate Cartilages
  3. 2 Cuneiform Cartilages
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25
Q

True Vocal Cords (AKA “Vocal Folds”)

A
  • Mucous membrane folds supported by elastic ligaments & are strung across rima glottidis
  • Contraction of lateral cricoarytenoid muscles -> adduction
  • Contraction of posterior cricoarytenoid muscles -> abduction
  • When air passes over true vocal cords -> vibration -> sound (phonation)
  • Tightening cords -> Higher pitch
  • Relaxing cords -> Lower pitch
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26
Q

4 Factors Affecting Pitch of Voice

A
  1. True vocal cord length
  2. Vocal cord thickness
  3. Vocal cord elasticity
  4. Vocal cord tension
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27
Q

Whispering

A

Only occurs when the small posterior portion of the rima is open

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28
Q

Loudness/Intensity of Voice

A
  • Determined by the amplitude of true vocal cord vibrations

- Amplitude of vibration corresponds to distance of travel of cords

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29
Q

Pitch/Frequency of Sound

A
  • Is the speed of vocal cord vibration
  • Corresponds to transit time, which is regulated by tension at which the cords are held by intrinsic laryngeal muscles
  • During puberty, larynx & vocal cord growth is rapid in males -> prominent thyroid cartilage & deeper voice
  • Vocal resonance from pharynx, oral & nasal cavities & paranasal sinuses
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30
Q

Vestibular Folds (AKA “False Vocal Cords”)

A
  • 2nd pair of folds, spanning the larger laryngeal opening (Rima Vestibuli)
  • Capable of full adduction
  • Inelastic & less delicate
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31
Q

Epithelial Lining of Larynx

A

Non-keratinized stratified squamous epithelium above vocal cords & “respiratory epithelium” below

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32
Q

Intrinsic Laryngeal Muscles

A
  • Regulate tension on true vocal cords
  • Open & close rima glottidiis
  • Posterior cricoarytenoid muscles -> abduction of true vocal cords
  • Lateral cricoarytenoid muscles -> adduction of true vocal cords
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33
Q

Extrinsic Laryngeal Muscles

A
  • Raise & lower thyroid cartilage
  • Sternothyroid muscles -> Depression of thyroid cartilage
  • Thyrohyoids muscles -> Elevation of thyroid cartilage
  • Ext. & int. laryng. muscles prevent food from entering the rima glottidis during swallowing
  • Coughing reflex expels foreign substances from entering rima glottidis
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34
Q

Heimlich Maneuver (AKA “Abdominal Thrust”)

A

First aid procedure for clearing obstructing objects from air passages

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35
Q

Laryngitis

A

Inflammation of the larynx

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36
Q

Laryngeal Cancer

A
  • A disease in which malignant (cancer) cells form in the tissues of the larynx
  • Can be caused by excessive alcohol & tobacco use
  • Sings & symptoms include sore throat & ear pain
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37
Q

Trachea (AKA “Windpipe”)

A
  • Rigid tube extending from C6 - T5, connecting larynx to primary bronchi at the carina
  • Composed of C-shaped hyaline cartilage rings (stiffening tracheal walls to prevent collapse)
  • Carina = last tracheal cartilage
  • Posterior tracheal wall contains “trachealis muscle” and no cartilage
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38
Q

“Respiratory Epithelium” Lining (Trachea)

A
  • Consists of pseudostratified ciliated columnar epithelium
  • Goblet cells produce mucous
  • Cilia help w/ mucociliary clearance of dirt, debris & microorganisms
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39
Q

Tracheostomy

A

An incision in the windpipe to relieve an obstruction in breathing

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40
Q

Intubation

A

The placement of a flexible plastic tube (“Endotracheal Tube”) into the trachea to maintain an open airway

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41
Q

Bronchial Tree

A

Consists of:
Trachea -> Right & left primary bronci -> Secondary lobar bronchi -> Tertiary segmental bronchi -> Bronchioles (20 generations) w/ the final generation = terminal bronchioles
*Primary bronchi = extrapulmonary
*Secondary & tertiary bronchi = intrapulmonary
*Each primary bronchus enters lung at hilum

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42
Q

4 Occurrences When Bronchioles Branch

A
  1. Amount of wall cartilage decreases
  2. Amount of bronchiolar smooth muscle increases
  3. Lumenal diameter decreases
  4. Epithelial type of mucosa changes
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43
Q

Broncho-constriction

A
  • Contraction of bronchioles

- Parasympathetic effect

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44
Q

Bronchodilation

A
  • Relaxation of bronchioles

- Sympathetic effect

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45
Q

4 Different Types of Epithelia (Bronchi & Bronchioles)

A
  1. Respiratory Epith. - Primary, secondary & tertiary bronchi
  2. Simple ciliated columnar epith. - Larger Bronchioles
  3. Simple ciliated cuboidal epith. - Smaller Bronchioles
  4. Simple cuboidal epith. - Terminal Bronchioles
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46
Q

Lungs

A

Organs of respiration separated by mediastinal structures

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47
Q

Parietal & Visceral Pleurae

A
  • The 2 pleural membranes surrounding each lung
  • Visceral = inner membrane surrounding the surface of each lung
  • Parietal = outer membrane attached to the inner surface of the thoracic cavity & diaphragm
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48
Q

Pneumothorax

A

The presence of air/gas in the cavity between the lungs and the chest wall, causing collapse of the lung

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49
Q

Hemothorax

A

A type of pleural effusion in which blood accumulates in the pleural cavity

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50
Q

Pleuritis

A

Inflammation of the membranes that surrounds the lungs and line the chest cavity

51
Q

Pleural Effusions

A

Excess fluid accumulation the pleural cavity

52
Q

Atelectasis

A

Partial/complete collapse of the lung (due to inflation)

53
Q

Thoracentesis

A

A procedure to remove excess fluid in the space between the lungs and the chest wall

54
Q

Primary Bronchi

A
  • Form secondary (lobar) bronchi which lead to each lobe of lung
  • Lung lobes separated by fissures
55
Q

Secondary Bronchi

A
  • Form tertiary (segmental) bronchi

- Each tertiary bronchus -> air to a single bronchopulmonary segment

56
Q

Differences Between Right & Left Lungs

A
  • Right lung: 3 lobes (superior, middle & inferior); separated by 2 fissures. Contains 10 bronchopulmonary segments
  • Left lung: 2 lobes (superior & inferior); separated by 1 fissure. Has 8 or 9 bronchopulmonary segments
57
Q

Bronchopulmonary Segments

A
  • Branch into bronchioles
  • Bronchioles branch to about 6,500 terminal bronchioles (Each -> single pulmonary lobule)
  • Approx. 124,000 terminal bronchioles or lobules/ 2 lungs
  • Elastic C.T. trabeculae extend into lung parenchyma from hilum & from visceral pleura -> branching -> elastic interlobar septa -> lobules
58
Q

4 Components of a Pulmonary Lobule

A
  1. A lymphatic vessel
  2. An arteriole
  3. A venule
  4. A terminal bronchiole & gas exchange airway
59
Q

Terminal Bronchioles

A
  • Branch into respiratory bronchioles
  • Epithelium changes from simple cuboidal -> simple squamous
  • Subdivide into 10 alveolar ducts, which end at alveolar sacs (composed of several individual alveoli
60
Q

Alveoli

A
  • Blind pockets composed of simple squamous epithelium

- Surrounded by capillary network

61
Q

Exchange of Respiratory Gases

A

Occurs when gases diffuse across alveolar-capillary (“respiratory”) membrane (Approx. 0.5 micrometers thick)

62
Q

4 Cell Types Associated w/ the Alveolus

A
  1. Type 1 Alveolar Cells: Squamous Pulmonary Epithelium
  2. Type 2 Alveolar Cells: Septal cells, secrete surfactant (decreases surface tension)
  3. Alveolar Macrophages: Provide immune defense
  4. Fibroblasts: Provide structural support
63
Q

Respiratory Distress Syndrome of the Newborn

A

A syndrome in premature infants caused by developmental insufficiency of pulmonary surfactant production and structural immaturity in the lungs

64
Q

Blood Supply to Lungs

A
  • Pulmonary Arteries: Carries O2-poor blood from heart to lungs
  • Bronchial Arteries: Supplies O2-rich blood to lungs
65
Q

Pulmonary Thromboembolism

A
  • A moving blockage of artery in the lungs

- Can lead to hemoptysis (coughing up of blood)

66
Q

Tissue Hypoxia

A
  • Lack of O2 supply to lung tissue
  • Leads to reflex vasoconstriction, increasing afterload on R. Ventricle -> possible congestive heart failure
  • Not logical to perfuse alveoli that are not ventilated (counterproductive)
67
Q

Ventilation-perfusion Coupling

A
  • The relationship between the amount of air reaching the air sacs of the lungs and the amount of blood reaching the lungs
  • Ventilation: Amount of O2 reaching alveoli
  • Perfusion: Amount of blood getting to the alveoli
68
Q

Pulmonary Ventilation

A
  • Movement of air in & out of lungs

- Consists of Inspiration (Inhalation) & Expiration (Exhalation)

69
Q

External Respiration

A
  • AKA “Pulmonary Respiration”

- Gas exchange across respiratory membranes in lungs

70
Q

Internal Respiration

A
  • AKA “Tissue Respiration”

- Gas exchange between capillary blood & peripheral tissue cells

71
Q

3 Components of the Thoracic Cavity

A
  1. Ribs
  2. Intercostal Muscles
  3. Diaphragm
72
Q

Respiratory Control Center

A
  • Primary nervous control of respiration

- Found in the reticular formation of the brain stem

73
Q

3 CNS Nuclei for Respiration

A
  1. Dorsal Respiratory Group
  2. Ventral Respiratory Group
  3. Pontine Respiratory Group
74
Q

Dorsal Respiratory Group

A
  • Stimulates inspiratory muscles: diaphragm & ext. intercostal muscles
  • For “quiet” breathing
  • DRG inactivity -> passive expiration
  • Found in medulla
75
Q

Ventral Respiratory Group

A
  1. Pre-Botzinger neuron complex = pacemaker; this area determines the rate of firing of DRG neurons -> inspiratory muscles
  2. Some VRG neurons -> forceful inhalation, causing accessory muscles of inhalation to contract (Driven by DRG)
  3. Other VRG neurons -> forceful exhalation, causing accessory muscles of exhalation to contract
    * Found in medulla
76
Q

Pontine Respiratory Group

A

PRG neurons target DRG neurons to alter basic rhythm of breathing
*Found in pons

77
Q

Central Chemoreceptors

A
  • Detect CO2 & H+ levels in CSF; determines breathing rate
  • When CO2 levels increase, H+ levels increase -> stimulation of medullary DRG -> Increased depth & rate of respiration
  • Not sensitive to normal decrease in O2 levels
78
Q

Peripheral Chemoreceptors

A
  • Carotid & aortic chemoreceptors detect hypoxemia, hypercapnia & acidosis
  • Any of the 3 above conditions cause peripheral chemoreceptors to stimulate DRG -> Increased rate & depth of respiration
79
Q

Hyperventilation

A
  • Increased ventilation depth & rate -> alkalosis
  • Often due to severe emotional stress
  • Low O2 stimulates DRG less than high CO2
80
Q

How Proprioceptors Affect Ventilation

A

Proprioceptors stimulate medullary DRG, increasing breathing rate & depth

81
Q

Mechanics of Normal Inspiration (Inhalation)

A
  • Medullary DRG -> nerve impulses to:
    1. Diaphragm (dome flattens)
    2. External Intercostals (moves ribs upwards & outwards)
82
Q

Forced Inhalation

A
  • Involves diaphragm & external intercostals
  • Also involves sternocleidomastoid, scalene & pectoralis minor muscles (accessory muscles)
  • The accessory muscles elevate sternum & ribs 1-5
83
Q

Overall Effect of Inhalation

A
  • Increased thoracic cavity dimensions -> Increased partial vacuum between pleurae -> Expansion of lungs
  • Amount of diaphragm flattening -> Increased amount of thoracic volume
  • At rest, inspiration = “Active Phase of Breathing” because it requires muscle contraction
84
Q

Boyle’s Law

A
  • Inverse relationship of gas volume & pressure

- When alveolar pressure decreases below atmospheric pressure, inspiration occurs

85
Q

Negative Pressure Ventilation

A
  • AKA “Iron Lung”

- A form of medical ventilator that enables a person to breathe when normal muscle control has been lost

86
Q

2 Possible Causes of Passive Expiration

A
  1. Quiet Breathing: Brief inactivity of medullary DRG
  2. Inflation Reflex: Excessive expansion of lungs -> bronchiolar baroreceptors send nerve impulses to inhibit the medullary DRG
    * In either case, diaphragm & ext. intercostal muscles relax
    * Expiration is normally considered passive
87
Q

2 Forces that Propel Air Outward

A
  1. Elastic recoil of thoracic wall & lungs
  2. Intra-alveolar fluid film surface tension (water film surface tension decreases alveolar volumes)
    * Decreased alveolar volumes cause increased alveolar pressure -> expiration
    * When alveolar pressure > atmospheric pressure -> expiration
    * Can also cause collapse of lung
88
Q

Active Expiration

A
  • Deep rapid breathing -> both inspiration & expiration active
  • Internal intercostal muscles -> “Forced Expiration”
  • Abdominal wall muscles (external & internal obliques + rectus abdominis) also active during active expiration
89
Q

2 Mechanisms Preventing Alveolar Collapse

A
  1. Surfactant = Detergent made by Type 2 Alveolar cells
  2. Sub-atmospheric intrapleural pressure (Intrapleural pressure normally < alveolar pressure -> alveoli partially inflated at end of expiration)
90
Q

3 Factors Affecting Rate of Respiratory Inflow

A
  1. Intra-alveolar fluid film surface tension
  2. Lung & thoracic compliance
  3. Airway resistance
91
Q

Lung & Thoracic Compliance

A
  • Ease w/ which lungs & thoracic wall expand

- Decreased compliance -> possible hypoxemia, hypercapnia, acidosis

92
Q

Airway Resistance

A
  • Exhalation -> Increased intra-thoracic pressure -> Decreased diameter of bronchioles -> Increased airway resistance
  • Airway obstruction & bronchoconstriction -> Increased airway resistance
  • COPD (emphysema & chronic bronchitis) -> Increased airway resistance
93
Q

Tidal Volume (TV)

A

Normally about 500 mL under resting conditions

*Minute ventilation at rest (500 mL x 12 breaths = 6L/min)

94
Q

Vital Capacity

A

Sum of inspiratory reserve volume, tidal volume & expiratory reserve volume

95
Q

Inspiratory Reserve Volume (IRV)

A

Extra air inspired above tidal volume

96
Q

Expiratory Reserve Volume (ERV)

A

Extra volume of air beyond tidal volume that can be exhaled forcibly

97
Q

Forced Expiratory Volume in 1 Second

A
  • AKA “FEV1”

- Maximal inhalation, then maximal exhalation

98
Q

Residual Volume (RV)

A

Volume of air still contained in lungs after a maximal expiration
*Increased in emphysema

99
Q

Anatomic Dead Space

A

Air that fills the conducting airways (About 150 mL); never reaches the lungs
*Breathing through a tube increases anatomic dead space & limits air pressure in lungs

100
Q

Alveolar Ventilation Rate at Rest

A

12 breaths x 350 mL = 4.2 L/min

101
Q

3 Other Lung Capacities

A
  1. Vital Capacity: IRV + TV + ERV
  2. Inspiratory Capacity: IRV + TV
  3. Total Lung Capacity: IRV + TV + ERV + RV
102
Q

Partial Pressure of a Gas

A

Pressure exerted by a certain gas in a mixture of gases

103
Q

Dalton’s Law

A

Each gas in a mixture exerts its own pressure as if all of the other gases were not present

104
Q

Atmospheric Pressure

A
  • Sum of all partial pressures of individual constituent gases
  • 760 mm Hg at Sea Level = 1 atmosphere
  • Nitrogen, oxygen, water vapor, argon and CO2 make up the atmospheric gases (Ordered from highest percentage to lowest)
105
Q

General Gas Law

A
  • Respiratory gases move from areas of higher pressure to lower pressure
  • The pressure of a gas determines its rate of diffusion
106
Q

Henry’s Law

A
  • If temperature is constant. quantity of a gas that will dissolve in a liquid is proportional to (1) its partial pressure and (2) its solubility coefficient
  • CO2 is 24x more soluble than O2
  • Higher solubility coefficient means better solubility in solution
107
Q

Hyperbaric Oxygen Therapy

A
  • Using oxygen at ambient pressure higher than atmospheric pressure
  • Forces increased oxygen into a patient’s blood
108
Q

Nitrogen Narcosis

A
  • When nitrogen concentrates in fatty tissues, creating a narcotic effect
  • Occurs when scuba divers remain at depths > 100 ft, causing N2 gas to be forced into solution in blood
109
Q

Decompression Sickness

A
  • A syndrome occurring in people working at great depths
  • If ascent too rapid, nitrogen dissolved in blood -> blood in tissues -> painful “bends” & potentially lethal gas embolisms
110
Q

O2 Partial Pressure in Lungs (External Respiration)

A
  • PO2 of alveolar air = 105 mmHg
  • PO2 of O2-poor blood = 40 mmHg
  • O2 diffuses from alveolus into pulmonary capillary
111
Q

CO2 Partial Pressure in Lungs (External Respiration)

A
  • PCO2 in alveolar air = 40 mmHg
  • PCO2 in O2-poor blood = 45 mmHg
  • CO2 diffuse out of blood into alveoli
112
Q

4 Factors Influencing External Respiration

A
  1. Partial pressures of gases in alveolar air & pulmonary capillary blood
  2. Large surface area for gas exchange of “respiratory” membrane
  3. Thickness of respiratory membrane
  4. Molecular weight & solubility of gases
113
Q

4 Factors Influencing Partial Pressures of Gases in Lungs

A
  1. Ventilation Rate: Rate of air inflow to lungs
  2. Lung Perfusion
  3. Metabolic Activity of Tissues: Determines O2 & CO2 levels
  4. Altitude: As elevation above sea level increases, O2 gradient decreases
114
Q

O2 Partial Pressure in Lungs (Internal Respiration)

A
  • PO2 of O2-rich arterial blood = 100 mmHg
  • PO2 of peripheral tissue cells = 40 mmHg
  • O2 diffuses from capillary into peripheral tissues
115
Q

CO2 Partial Pressure in Lungs (Internal Respiration)

A
  • PCO2 of O2-rich arterial blood = 40 mmHg
  • PCO2 of peripheral tissues = 45 mmHg
  • CO2 diffuses out of tissues into blood
116
Q

2 Modes of O2 Transport

A
  1. O2 dissolving in plasma (1.5% of O2)
  2. O2 carried by heme of RBC hemoglobin (98.5% of O2)
    * O2 turns hemoglobin into oxyhemoglobin
    * Hb w/ reduced O2 -> deoxyhemoglobin
117
Q

Rule for O2 binding to Hb

A
  • The higher the PO2, the more O2 binds Hb
  • At PO2 of alveolar air, Hb is approx. 100% saturated w/ O2
  • At PO2 of most peripheral tissues, Hb releases some bound oxygen
  • Hb also more readily releases O2 in actively metabolizing tissues (warmer & more acidic)
118
Q

5 Factors Affecting O2 & Hb association

A
  1. PO2 of alveolar air
  2. Acid pH (Bohr Effect)
  3. PCO2 of arterial blood
  4. Temperature
  5. 2,3, - biphosphoglycerate
  • Increase of 1 causes shift to left, causing increased O2-Hb affinity (& vice-versa)
  • Increase of 2,3,4 and 5 causes shift to right, causing decreased O2-Hb affinity, leading to more O2 to tissues (& vice-versa)
119
Q

Fetal Hb (Hb-F)

A
  • Has greater affinity for O2 than adult Hb
  • When PO2 is low, fetal Hb carries 20-30% more O2 than maternal Hb
  • Allows maternal blood to transfer O2 to fetal blood in the placenta
120
Q

Carbon Monoxide Poisoning

A
  • CO = by-product of incomplete oxidation of hydrocarbons
  • Problem: CO’s affinity for Hb is > 200x O2’s Hb affinity
  • 0.1% CO can compete w/ atmospheric O2 (21%)
121
Q

3 Modes of CO2 Transport

A
  1. 7% dissolves in plasma
  2. 23% combines w/ Hb -> Carbaminohemoglobin
  3. 70& transported as HCO3-
122
Q

HCO3- Formation/Equation

A

CO2 + H2O H2CO3 H+ + HCO3-

  • RBC Carbonic anhydrase speeds up the reaction
  • H+ ions released by the reaction are buffered by globin portion
  • Underlies Bohr effect which states that Hb’s O2 binding affinity is inversely related to acidity
123
Q

2 Methods of Chloride Shift in Periphery

A
  1. HCO3- ions diffuse out of RBCs & carried in plasma

2. Chloride (Cl-) ions from plasma enter RBCs

124
Q

2 Methods of Chloride Shift in Lungs

A
  1. HCO3- ions diffuse back into RBCs
  2. Cl- diffuses out of RBCs & back into plasma
    * CO2 diffuses out of blood into alveoli for expiration
    * RBC Hb is again available to transport O2

BIOL1191 (13 decks)

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