Chapter 23: The Respiratory System Flashcards

Question

Laryngopharynx

Answer 1

- passageway for food, fluids and air - begins from level of hyoid bone to the esophagus - anteriorly, lies the larynx - lined with nonkeratinized stratified squamous epithelium

Answer 2

1. Adequate Surface Area for Gas Exchange - lungs have alvelor sacs that increases surface area 2. Adequate Transport System - RBC's 3. Adequate Protection - mucous membranes and wandering macrophages throughout the respiratory tract 4. Adequate Moisture - surfactant is produced inside lunges (allows expansion and recoil of alveolar sacs)

Answer 3

1. bring oxygen rich air into the body for cells 2. expel waste products (CO2 & H2o) from the body 3. produce air flow that makes speech possible

Answer 4

1. Respiratory Zone - site of gas exchange (consists of respiratory bronchioles, alveolar ducts and alveoli) 2. Conducting Zone - conduits that transport gas to and from gas exchange sites (cleanses, warms and humidifies air)

Answer 5

- extends from 4th/5th to 6th cervical vertebra and attaches to hyoid bone - connects the laryngopharynx with the trachea - consists of 9 cartilages connected by membranes and ligaments

Answer 6

1. Provide patent airway 2. Routes air and food into proper channels 3. Voice Production (houses vocal folds)

Answer 7

1. Thyroid cartilage: (Adam's Apple) 2. Cricoid cartilage: ring-shaped 3 & 4. Paired Arytenoid cartilages 5 & 6. Paired Cuneiform cartilages 7 & 8. Paired Corniculate Cartilages 9. Epiglottis

Answer 8

- aka Vocal Folds: formed by vocal ligaments - contain elastic fibers that appear white because lack of blood vessels - glottis: opening between vocal folds - folds vibrate to produce sound as air rushes up from lungs

Answer 9

- aka False Vocal Cords - superior to vocal folds - no part in sound production - help to close glottis during swallowing and function in holding breath against pressure in thoracic cavity

Answer 10

intermittent release of expire air during opening and closing of glottis

Answer 11

determined by diameter, length and tension of vocal cords

Answer 12

depends upon force of air as it rushes through the vocal cords. - chambers of pharynx and oral, nasal and sinus cavities amplify and enhance sound quality - sound is shaped into language by muscles of pharynx, tongue, soft palate and lips

Answer 13

- Windpipe - extends from larynx into mediastinum, where it divides into the left and right primary bronchi - it is about 4-5 inches long, 1 inch in diameter and flexible

Answer 14

1. mucosa: psuedostratified ciliated columnar epithelium with goble cells and underlying layer of lamina propria 2. submucosa: areolar connective tissue with seromucous glands 3. adventitia: outermost layer made of areolar connective tissue. Reinforced internally by 16-20 C-shaped hyaline cartilage rings prevent collapse of trachea.

Answer 15

integral part of the body's airway and has the vital function of providing air flow to and from the lungs for respiration

Answer 16

hemoglobin combined with oxygen

Answer 17

hemoglobin that has release O2

Answer 18

when only one to three hemes carry O2

Answer 19

all four heme groups carry O2

Answer 20

- amount of CO2 transported is affected by P O2 | - The lower the P O2 and hemoglobin O2 saturation, the more CO2 can be carried in blood

Answer 21

inadequate O2 delivery to tissues, can result in cyanoses

Answer 22

- pressure that keeps lung spaces open (keeps lungs from collapsing) - the greater transpulmonary presssure -> the larger the lungs will be - (P pul - P ip )

Answer 23

lungs collapse due to: - plugged bronchioles, which cause collapse of alveoli or - pneumothorax

Answer 24

- air in pleural cavity - can occur from either wound in parietal pleura or rupture of visceral pleura - treated by removing air with chest tubes - when pleurae heal, lung reinflates

Answer 25

inflammation of pleurae that often results from pneumonia | -inflamed pleurae become rough, resulting in friction and stabbing pain with each breath

Answer 26

increased depth and rate of breathing that exceeds body's need to remove CO2 - may be caused by anxiety attacks - leads to decreased blood CO2 levels - treatment: breathing into paper bag increases CO2 levels being inspired

Answer 27

breathing cessation that may occur when P CO2 levels drop abnormally low

Answer 28

bronchial tree

Answer 29

-the branching system of bronchi and bronchioles conducting air from the windpipe into the lungs. -From the tips of the bronchial tree: Conducting zone structures -> Respiratory zone structures

Answer 30

- Trachea divides to form right and left main (primary) bronchi - Each main bronchus enters hilum of one lung - Each main bronchus then branches into lobar (secondary) bronchi - Each lobar bronchus branches into segmental (tertiary) bronchi - Branches become smaller and smaller: Bronchioles and Terminal Bronchioles

Answer 31

right main bronchus: wider, shorter and more vertical than the left

Answer 32

- three on the right and two on the left | - each lobar bronchus supplies one lobe

Answer 33

- supply specific bronchopulmonary segments within each lobe of lung - segmental bronchi divide repeatedly

Answer 34

- smallest of all conducting zone structures | - less than 0.5 mm in diameter

Answer 35

- cartilage rings become irregular plates and in bronchioles, elastic fibers replace cartilage - Psuedostratified ciliated columnar changes to simple cuboidal. - Cilia and goblet cells become more sparse - Amount of smooth muscle increases

Answer 36

- begin where terminal bronchioles feed into respiratory branchioles - leads to alveolar ducts - then into alveolar sacs (saccules)

Answer 37

- aka lobules - contain clusters of alveoli - Sites of actual gas exchange - about 300 million alveoli make up mosat of lung volume

Answer 38

first place where gas exchange can occur

Answer 39

- Surrounded by fine elastic fibers and pulmonary capillaries - Alveolar pores connect adjacent alveoli

Answer 40

- Equalize air pressure throughout lung - Provide alternate routes in case of blockages - Alveolar macrophages keep alveolar surfaces sterile

Answer 41

- allows for rapid gas exchange across membrane by simple diffusion - Blood air barrier

Answer 42

- lowers surface tension of alveolar fluid, preventing the collapse of alveoli with each expiration/breath - allows the expansion and recoil of the alveolar sacs - produced by type ii alveolar sacs

Answer 43

- Root - Costal Surface - Apex - Base - Hilum

Answer 44

- separated into superior and inferior lobes by oblique fissure - Smaller than right because of position of heart - Has Cardiac notch

Answer 45

concavity in the left lung for the heart to fit into

Answer 46

- separated into superior, middle, and inferior lobes - Superior and middle lobes separated by horizontal fissure - Middle and inferior lobes separated by oblique fissure

Answer 47

site of vascular and bronchial attachment to mediastinum

Answer 48

anterior, lateral, and posterior surfaces

Answer 49

superior tip, deep to clavicle

Answer 50

inferior surface that rests on diaphragm

Answer 51

- found on mediastinal surface | - it is the site for entry/exit of blood vessels, bronchi, lymphatic vessels, and nerves

Answer 52

Bronchopulmonary Segments

Answer 53

- Separated by connective tissue septa - Each segment is served by its own artery, vein, and segmental (tertiary) bronchus - If one segment is diseased, it can be individually removed

Answer 54

-10 on right and 8–10 on left

Answer 55

``` Gas exchange Filtration Blood reservoir Metabolic Thermal ```

Answer 56

- alveoli; the rest consists of stroma, elastic connective tissue - Makes lungs very elastic and spongy

Answer 57

1. Pulmonary Circulation | 2. Bronchial Circulation

Answer 58

- Pulmonary arteries - deliver systemic venous blood from heart to lungs for oxygenation - Branch profusely to feed into pulmonary capillary networks - Pulmonary veins - carry oxygenated blood from respiratory zones back to heart (Low-pressure, high-volume system)

Answer 59

- provide oxygenated blood to lung tissue - Arise from aorta and enter lungs at hilum - Part of systemic circulation, so are high pressure, low volume - Supply all lung tissue except alveoli - Bronchial veins anastomose with pulmonary veins

Answer 60

thin, double-layered serosal membrane that divides thoracic cavity into two pleural compartments and mediastinum

Answer 61

membrane on thoracic wall, superior face of diaphragm, around heart, and between lungs

Answer 62

membrane on external lung surface

Answer 63

- fills slit-like pleural cavity between two pleurae | - Provides lubrication and surface tension that assists in expansion and recoil of lungs

Answer 64

inflammation of pleurae that often results from pneumonia

Answer 65

fluid accumulation in pleural cavity

Answer 66

- Pressure exerted by air surrounding the body | - 760 mm Hg at sea level = 1 atmosphere (1 atm)

Answer 67

less than Patm

Answer 68

greater than P atm

Answer 69

equal to P atm

Answer 70

- Pressure in alveoli - Fluctuates with breathing - Always eventually equalizes with P atm

Answer 71

- Pressure in pleural cavity - Fluctuates with breathing - Always a negative pressure (

Answer 72

If fluid accumulates, positive P ip pressure develops: Lung collapses

Answer 73

P ip = P pul | P ip = P atm

Answer 74

Intrapleural Pressure (P ip)

Answer 75

pressure changes

Answer 76

to flow of gases to equalize pressure

Answer 77

the diaphragm and external intercostals

Answer 78

- when dome-shaped diaphragm contracts, it moves inferiorly and flattens out - Results in increase in thoracic volume

Answer 79

- when external intercostals contract, rib cage is lifted up and out - Results in increase in thoracic volume

Answer 80

normally is passive process

Answer 81

is an active process that uses oblique and transverse abdominal muscles, as well as internal intercostal muscles

Answer 82

- Inspiratory muscles relax, thoracic cavity volume decreases, and lungs recoil - Volume decrease causes intrapulmonary pressure (Ppul) to increase by +1 mm Hg - Ppul > Patm so air flows out of lungs down its pressure gradient until Ppul = Patm - P ip goes from -6 to -4 mm of Hg

Answer 83

- As thoracic cavity volume increases, lungs are stretched as they are pulled out with thoracic cage - Causes intrapulmonary pressure to drop by 1 mm Hg (-1mm Hg) - Ppul - P ip goes from -4 to -6 mm Hg

Answer 84

- Gases always fill the container they are in - If amount of gas is the same and container size is reduced, pressure will increase - Pressure (P) varies inversely with volume (V)

Answer 85

influence the ease of air passage and the amount of energy required for ventilation: i. Airway resistance ii. Alveolar surface tension iii. Lung compliance

Answer 86

- Relationship between flow (F), pressure (P), and resistance (R) - As airway resistance rises, breathing movements become more strenuous - Severe constriction or obstruction of bronchioles

Answer 87

dilates bronchioles, reduces air resistance

Answer 88

- Surface tension: the attraction of liquid molecules to one another at a gas-liquid interface - Tends to draw liquid molecules closer together and reduce contact with dissimilar gas molecules - Resists any force that tends to increase surface area of liquid

Answer 89

- Water, which has very high surface tension, coats alveolar walls in a thin film - Tends to cause alveoli to shrink to smallest size and causes it to collapse

Answer 90

- measure of change in lung volume that occurs with given change in transpulmonary pressure - Measure of how much “stretch” the lung has

Answer 91

- Normally high because of: - Distensibility of lung tissue - Surfactant, which decreases alveolar surface tension - Higher lung compliance means it is easier to expand lungs

Answer 92

- Nonelastic scar tissue replacing lung tissue (fibrosis: tuberculosis) - Reduced production of surfactant - Fluid or mucus buildup in lung or in respiratory passages - Decreased flexibility of thoracic cage

Answer 93

1. Tidal Volume (TV) 2. Inspiratory Reserve Volume (IRV) 3. Expiratory Reserve Volume (ERV) 4. Residual Volume (RV)

Answer 94

~ 500 mL | -the amount of air that moves in and out with each breath while at rest

Answer 95

2100 – 3200 mL | -the maximum volume of air that can be inhaled forcibly beyond the tidal volume

Answer 96

1000 – 1200 mL | -the maximum volume of air that can be exhaled forcibly beyond the tidal volume

Answer 97

the amount of air remaining in the lungs after exhalation (keeps the lungs from collapsing in between breaths)

Answer 98

1. Inspiratory Capacity (IC) 2. Functional Residual Capicity (FRC) 3. Vital Capacity (VC) 4. Total Lung Capacity (TLC)

Answer 99

IC = TV + IRV

Answer 100

FRC = RV + ERV

Answer 101

VC = TV + IRV + ERV

Answer 102

TLC = TV + IRV + ERC + RV

Answer 103

- Perfusion: blood flow reaching alveoli - Ventilation: amount of gas reaching alveoli Ventilation and perfusion rates must be matched for optimal, efficient gas exchange Both are controlled by local autoregulatory mechanisms

Answer 104

- PO2 controls perfusion by changing arteriolar diameter | - PCO2 controls ventilation by changing bronchiolar diameter

Answer 105

At tissues, as more CO2 enters blood, more oxygen dissociates from hemoglobin

Answer 106

- Symptoms include frequent pulmonary infections | - Risk factors include smoking and environmental pollutants

Answer 107

- Inhaled irritants cause chronic excessive mucus - Mucosae of lower respiratory passageways become inflamed and fibrosed - Results in obstructed airways that impair lung ventilation and gas exchange

Answer 108

- Infectious disease caused by bacterium Mycobacterium tuberculosis - Symptoms: fever, night sweats, weight loss, racking cough, coughing up blood - Treatment: 12-month course of antibiotics

Answer 109

Leading cause of cancer deaths in North America | 90% of all cases are result of smoking

Answer 110

1. Adenocarcinoma (~40% of cases) 2. Squamous cell carcinoma (20–40% of cases) 3. Small cell carcinoma (~20% of cases)

Answer 111

originates in peripheral lung areas; develops from bronchial glands and alveolar cells

Answer 112

arises in bronchial epithelium

Answer 113

contains lymphocyte-like cells that originate in primary bronchi and subsequently metastasize

Answer 114

- Characterized by coughing, dyspnea, wheezing, and chest tightness - Active inflammation of airways precedes bronchospasms - Airways thickened with inflammatory exudate magnify effect of bronchospasms

Answer 115

- Permanent enlargement of alveoli and destruction of alveolar walls result in decreased lung elasticity, with three consequences. - Hereditary factors for disease include alpha-1 antitrypsin deficiency

Answer 116

1. Accessory muscles are necessary for breathing, leading to exhaustion from using 10–15% more energy to breathe than normal 2. Trapped air causes hyperinflation, which flattens diaphragm and causes expanded barrel chest, both of which reduces ventilation efficiency 3. Damaged pulmonary capillaries lead to enlarged right ventricle

Answer 117

- Exemplified by chronic emphysema and chronic bronchitis - Key feature is irreversible decrease in ability to force air out of lungs - Dyspnea: labored breathing (“air hunger”) - Coughing and frequent pulmonary infections - Most patients develop hypoventilation accompanied by respiratory acidosis, hypoxemia

Answer 118

o “The Bends” o Formation of bubbles in the bloodstream (nitrogen), accumulate in joints o Caused by rapid decrease in pressure (nitrogen gas, similar to soda)

Answer 119

A decreased amount of air entering the lungs, resulting in reduced blood oxygen content, increased blood carbon dioxide content, or both

Answer 120

surgical incision into trachea for purpose of establishing an airway

Answer 121

The plasma membrane of the RBC passively facilitates the diffusion of bicarbonate ions out of the RBC and chloride ions into the RBC

Answer 122

- occur during vigorous exercise or in people with COPD - Accessory muscles are activated which further increase thoracic cage size, creating a larger pressure gradient so more air is drawn in.

Answer 123

Only occurs during forced inspirations - scalenes - sternocleidomastoid - pectoralis minor - serratus anterior

Answer 124

does not contribute to gas exchange. | Consists of air that remains in passageways (RV)

Answer 125

- space occupied by nonfunctional alveoli | - can be due to collapse or obstruction

Answer 126

sum of anatomical and alveolar dead space

Answer 127

- increased airway resistance. | - TLC, FRC, RV may increase because of hyperinflation of lungs

Answer 128

- reduced TLC due to disease (ex TB) or exposure to environment agents - VC, TLC, FRC, RV decline because lung expansion is compromised

Answer 129

diffusion of gases between blood and lungs

Answer 130

diffusion of gases between blood tissues

Answer 131

1. Basic properties of gases | 2. Composition of gases

Answer 132

total pressure exerted by mixture of gases is equal to sum of pressures exerted by each gas

Answer 133

- pressure exerted by each gas in mixture | - directly proportional to its percentage mixture

Answer 134

can be calculated: 0.786 x 760 mm Hg (atm) = 597 mm Hg

Answer 135

0.209 x 760 mm of Hg (atm) = 159 mm Hg

Answer 136

for gas mixtures in contact with liquids: - each gas will dissolve in the liquid in proportion to its partial pressure and its solubility - at equilibrium, partial pressures in two phases will be equal

Answer 137

Solubility, Pressure (increase pressure, increase solubility) and Temperature (temp of liquid rises, solubility decreases)

Answer 138

exchange of O2 and CO2 across respiratory membranes

Answer 139

1. partial pressure gradients and solubilities 2. thickness and surface area of respiratory membrane 3. Ventilation-perfusion coupling

Answer 140

= 104 mm Hg - drives oxygen flow into blood - equilibrium reached across respiratory membrane in ~0.25 sec, but it takes RBC ~0.75 sec to travel from start to end of pulmonary capillary (ensures adequation oxygenation even if blood flow increases 3x)

Answer 141

- determined by how actively respiratory center stimulates respiratory muscles - The greater the stimulation, the greater the number of motor units excited, increasing depth of inspiration

Answer 142

- determined by how long center is active | - Both are modified by changing body demands

Answer 143

i. Chemical factors ii. Influence of higher brain centers iii. Pulmonary irritant reflexes iv. Inflation reflex

Answer 144

- Most important of all factors affecting depth and rate of inspiration - Changing levels of PCO2, PO2, and pH are most important

Answer 145

central chemoreceptors and peripheral chemoreceptors

Answer 146

-CO2 accumulates in brain and joins with water to become carbonic acid -Carbonic acid dissociates, releasing H+, causing a drop in pH (increased acidity) -Increased H+ stimulates central chemoreceptors & peripheral chemoreceptors  Respiratory centers increase depth and rate of breathing, which act to lower blood PCO2, and pH rises to normal levels

Answer 147

respiration becomes slow and shallow

Answer 148

- Hypothalamic controls: act through limbic system to modify rate and depth of respiration - Cortical controls: direct signals from cerebral motor cortex that bypass medullary controls

Answer 149

- Receptors in bronchioles respond to irritants such as dust, accumulated mucus, or noxious fumes - Receptors communicate with respiratory centers via vagus nerve (sensory) - Promote reflexive constriction of air passages - Same irritant triggers a cough in trachea or bronchi or a sneeze in nasal cavity

Answer 150

- Stretch receptors in pleurae and airways are stimulated by lung inflation - Send inhibitory signals to medullary respiratory centers to end inhalation and allow expiration - May act as protective response more than as a normal regulatory mechanism