Respiratory physiology Flashcards

Question

explain the conditioning of air function of the conducting zone

Answer 1

inspired air is adjusted to body temperature and saturated with water vapour by the time it reaches the trachea during nasal breathing

Answer 2

particulate matter in inspired air is removed by several mechanisms: -Filtration: as inspired gas passes through the nose, nasal vibrissae (coarse hairs) filters out particles that are larger than 50µ in diameter. -Impaction: by impaction on the walls of the upper airways (the momentum of these particles cause them to stick to the mucous lining of the airways), particles that are 2-50µm in diameter are removed from inspired gas -Sedimentation: particles that are 0.01-2µm are largely deposited in the small airways (where flow velocity is very low) and alveoli because of the effect of gravity -Diffusion: inflammation develops and thus the activation of macrophages when particles less than 0.01µm reach the walls of the terminal airways and alveoli by diffusion.

Answer 3

as inspired gas passes through the nose, nasal vibrissae (coarse hairs) filters out particles that are larger than 50µ in diameter.

Answer 4

by impaction on the walls of the upper airways (the momentum of these particles cause them to stick to the mucous lining of the airways), particles that are 2-50µm in diameter are removed from inspired gas

Answer 5

particles that are 0.01-2µm are largely deposited in the small airways (where flow velocity is very low) and alveoli because of the effect of gravity

Answer 6

inflammation develops and thus the activation of macrophages when particles less than 0.01µm reach the walls of the terminal airways and alveoli by diffusion.

Answer 7

-Irritant receptors are located in the large bronchi, they are stimulated by foreign materials -This leads to reflex bronchoconstriction, cough, and increase secretion of mucous -Foreign particles and vapour which reach the alveolar surface leads to the presence of increased alveolar macrophages which in turn releases proteolytic enzymes into the lung tissue (proteolytic enzymes are also called proteinase: they break long chain of protein molecules into shorter fragments-peptides-and eventually into amino acids).

Answer 8

check the book

Answer 9

Respiratory bronchiole (17-19) Alveolar ducts (20-22) Alveolar sac/alveoli (23)

Answer 10

branches of pulmonary artery

Answer 11

Primarily in gas exchange across the respiratory membrane (ie between alveolar gas and pulmonary capillary blood, by the process of diffusion).

Answer 12

-Olfaction -Vocalization -Prevention of foreign particles entering the lungs: By filtration, macrophages, cough reflex, sneeze reflex. -Immunity: leucocytes, macrophages, lung defensins, lung cathelidicins, mast cells, dendritic cells, Natural killer cells. -Maintainance of water balance by expiration -regulation of body temperature: by expiration -regulation of acid-base balance -anticoagulant: mast cells secrete heparin -secretion of angiotensin converting enzyme -secretion of hormones: serotonin, prostaglandins, acetylcholine

Answer 13

Also called the tracheobronchial tree. It refers to the branching structure of airways supplying air to the lungs, and includes: Trachea Main bronchus Lobar bronchus Segmental bronchus Conducting bronchiole Terminal bronchiole Respiratory bronchiole Alveolar duct Alveolar sac alveolus

Answer 14

1. Location: The respiratory tract extends from the nose/mouth down to the lungs, while the respiratory tree is located within the lungs. 2. Function: The respiratory tract is responsible for conducting air into and out of the lungs, while the respiratory tree is responsible for distributing air within the lungs and facilitating gas exchange. 3. Structure: The respiratory tract includes several structures such as the nasal cavity, pharynx, larynx, trachea, bronchi and bronchioles. The respiratory tree is a network of progressively smaller tubes, starting with the main bronchi and branching out into smaller bronchioles. 4. Size: The respiratory tract is generally larger in diameter than the respiratory tree, which consists of progressively smaller tubes as they branch out. 5. Composition: The respiratory tract is lined with a variety of tissues including mucous membranes, cartilage, and smooth muscle. The respiratory tree is composed of smooth muscle, elastic fibers, and a thin layer of epithelial cells. 6. Cross sectional area: The respiratory tract has a smaller cross sectional area than the respiratory tree. (2.5cm2 < 11800cm2)

Answer 15

The trachea and bronchus

Answer 16

11 are epithelial cells, and 2 are mesenchymal cells

Answer 17

are abundant in the upper RT, but fewer down, and absent in the bronchioles.

Answer 18

most of the epithelium is covered in ciliated pseudostratified columnar epithelium

Answer 19

the throat

Answer 20

the bronchioles, where it is replaced with smooth muscle

Answer 21

hyaline cartilage (the rigid cartilage prevents the bronchi from collapsing and blocking airflow to the lungs)

Answer 22

ciliated pseudostratified epithelium

Answer 23

They constrict to prevent pollution from dust and other pollutants.

Answer 24

during exercise, to let more air in

Answer 25

-Respiration -Alter the pH of blood by facilitating alterations in the partial pressure of CO2 -Converts angiotensin I to angiotensin II by the action of angiotensinogen-converting enzyme -Serves as a reservoir of blood in the body, blood volume of the lung is about 9% of the total blood volume of the entire circulatory system. -Serves as a layer of soft, shock-absorbent protection for the heart which the lungs flank and nearly enclose

Answer 26

simple squamous epithelium, (TYPE I)

Answer 27

Septal cells produce alveolar fluid/pulmonary surfactant which coats the inner surface of the alveoli, helps to maintain the elasticity of the lungs, and prevents the thin alveolar walls from collapsing. -They also help stabilise the alveoli

Answer 28

Macrophages in the alveoli keep the lungs clean and free of infections by capturing and phagocytizing pathogens and other foreign matter that enter the alveoli along with inhaled air

Answer 29

the volume of air left in the respiratory tract after the most forceful expiration. (1200mL)

Answer 30

-Prevents collapse of the airways/lungs -It allows for gas exchange even in periods of low ventilation (such as in sleep)

Answer 31

alveoli air

Answer 32

the air pressure changes within the lungs

Answer 33

inspiration also called inhalation is the active process of breathing air from the mouth/nose, through the respiratory tract, and into the lungs

Answer 34

Normal quiet breathing, also known as resting or tidal breathing, is the process of breathing that occurs during rest or light activity. During normal quiet breathing, the diaphragm and other muscles involved in respiration contract and relax in a rhythmic pattern to move a small amount of air in and out of the lungs. The volume of air moved in and out with each breath is relatively small, typically around 500 mL, and the frequency of breaths is relatively low, typically around 12-20 breaths per minute. Normal quiet breathing is sufficient for maintaining normal levels of oxygen and carbon dioxide in the blood during rest or light activity. It is an involuntary process that is controlled by the respiratory center in the brainstem and can be influenced by factors such as -emotions, -stress, and -physical activity.

Answer 35

Forced breathing, also known as hyperpnea, is the process of breathing that occurs when the body's demand for oxygen increases, such as during exercise or in response to respiratory distress. During forced breathing, the respiratory muscles work harder and contract more forcefully to move a larger volume of air in and out of the lungs. This increased effort requires more energy and can be achieved through the use of additional muscles (accessory muscles of respiration). Forced breathing can also involve an increase in respiratory rate (breaths per minute) to meet the increased demand for oxygen. Forced breathing is an active process that requires conscious effort and can feel more uncomfortable or difficult than normal quiet breathing. It is necessary for maintaining adequate levels of oxygen in the body during periods of increased demand (such as in exercise) or respiratory compromise.

Answer 36

-Diaphragm -External intercostal

Answer 37

-A dome-shaped muscle supplied by 2 phrenic nerves -Its contraction causes an increase in the superior-inferior diameter of the thoracic cavity (contraction of the diaphragm involves its lowering to a more flattened shape; this increases the thoracic volume and thus increases lung volume and thus reduces lung pressure) -Contraction of the diaphragm accounts for 2/3rd of the air that flows into the lungs in quiet inspiration and 75% of the change in intrathoracic volume during quiet inspiration. -Contraction of the diaphragm is limited by -advanced pregnancy, -obesity, and -tight abdominal clothing

Answer 38

-advanced pregnancy -obesity -overeating -tight abdominal clothing

Answer 39

This muscle runs obliquely downward and forward from rib to rib On contraction, it elevates the lower ribs, thus pushing the sternum outward and thus increase the anterior-posterior diameter of the chest The transverse diameter also increases, but to a lesser degree This elevating the ribs and expansion of the rib cage also increases the thoracic volume Contraction of the external intercostal muscle accounts for the remaining 1/3rd of air that fills the lungs during normal quiet breathin

Answer 40

-diaphragm -external intercostal

Answer 41

These group of muscles are usually called to play in forced inspiration. They include; -Scalene -Sternocleidomastoid -Alae Nasi -Small muscles of the head and neck -Elevators of the scapula and pectoralis major -In forced/deep inspiration, these muscles on contraction elevate the ribs in an anteroposterior direction (thus increasing thoracic volume) -At the same time, their contraction stabilizes the upper rib cage so that the external intercostal muscle becomes more effective

Answer 42

-In forced/deep inspiration, these muscles on contraction elevate the ribs in an anteroposterior direction (thus increasing thoracic volume). -At the same time, their contraction stabilizes the upper rib cage so that the external intercostal muscle becomes more effective

Answer 43

No muscle which causes reduced intrathoracic volume contract Normal expiration results from muscle relaxation and elastic recoil of lungs and thoracic cage In expiration, the reduction in lung volume that results raises the pressure within the alveoli above the atmospheric pressure, this pushes air out of the lungs into the atmosphere

Answer 44

expiration also called exhalation is the removal of air, containing the by-products of respiration from the lungs, through the respiratory tract, out of the nose/mouth

Answer 45

Rectus abdominis muscle Transversus abdominis muscle Internal oblique muscle External oblique muscle Internal Intercostal Muscle (on contraction, it depresses the rib cage)

Answer 46

-During forced expiration, these anterior abdominal wall muscles by their contraction force abdominal organs up against the diaphragm thus further reducing the volume in the thorax -This way, alveolar pressure within the pleural cavities can raise to 20mmHg or 30mmHg above atmospheric pressure

Answer 47

The pressure of a given mass of gas is inversely proportional to its volume

Answer 48

The pressure of a given mass of gas is inversely proportional to its volume

Answer 49

-During inspiration, the diaphragm and the external intercostal muscles contract. The diaphragm increases the superior-inferior volume of the thoracic cavity, when it contracts and the external intercostals increases the anterior-posterior volume of the thorax (and also the transverse). -As the thoracic volume increases, the intrapleural pressure reduces -Inspiration begins when the alveolar reduces below atmospheric pressure, by 2.5mmHg. This is because the reduction of intrapleural pressure, increases alveolar volume and thus reduces alveolar pressure -Thus air flows into the lungs, because the alveolar pressure is lower than the atmospheric pressure

Answer 50

-During inspiration, the diaphragm and the external intercostal muscles contract. The diaphragm increases the superior-inferior volume of the thoracic cavity, when it contracts and the external intercostals increases the anterior-posterior volume of the thorax (and also the transverse). -As the thoracic volume increases, the intrapleural pressure reduces -Inspiration begins when the alveolar reduces below atmospheric pressure, by 2.5mmHg. This is because the reduction of intrapleural pressure, increases alveolar volume and thus reduces alveolar pressure -Thus air flows into the lungs, because the alveolar pressure is lower than the atmospheric pressure

Answer 51

-During expiration, the diaphragm and any other muscles involved relax, and the thoracic volume reduces -The reduction of intrathoracic volume, increases the intrapleural pressure -As expiration begins, the alveolar pressure is higher than the atmospheric pressure, by 3mmHg. Thus is because the increased intrapleural pressure, reduces the alveolar volume, and thus increases the alveolar pressure. -Thus air flows out of the lungs because the alveolar pressure is greater than the atmospheric pressure.

Answer 52

1. Volume of air: During normal quiet breathing, only a small amount of air is moved in and out of the lungs with each breath, while during forced breathing, a larger volume of air is moved in and out of the lungs. 2. Frequency of breaths: During normal quiet breathing, the frequency of breaths is relatively low (typically around 12-20 breaths per minute), while during forced breathing, the frequency of breaths may increase. 3. Muscles used: In normal quiet breathing, accessory muscles are not involved. In forced breathing the accessory muscles are involved 4. Energy expenditure: Forced breathing requires more energy than normal quiet breathing due to the increased use of muscles. 5. Purpose: Normal quiet breathing is sufficient for maintaining normal levels of oxygen and carbon dioxide in the blood during rest or light activity, while forced breathing is necessary during periods of increased demand such as exercise or when respiratory function is compromised due to illness or injury. 6. Lung capacity: Forced breathing can utilize a larger portion of lung capacity than normal quiet breathing, which typically only uses about 10% of total lung capacity. 7. Airflow: During forced breathing, airflow through the airways increases due to the increased volume of air being moved in and out of the lungs. 8. Gas exchange: Forced breathing may result in greater gas exchange due to the increased airflow and volume of air being moved in and out of the lungs. 9. Respiratory rate: During forced breathing, respiratory rate may increase to meet the increased demand for oxygen. 10. Sensation: Forced breathing can feel more uncomfortable or difficult than normal quiet breathing due to the increased effort required to move air in and out of the lungs. 11. In normal quiet breathing, the expiration is passive. In forced breathing, expiration is active

Answer 53

The work of breathing refers to the amount of energy required to move air in and out of the lungs during respiration

Answer 54

This is because expiration is a passive process that requires no energy (except in forced expiration)

Answer 55

3 parts: -compliance -tissue resistance -airway resistance

Answer 56

it is the ability of the lungs to expand against the lungs and chest elastic forces. It is simply the ability of the lungs to expand, according to changes in pressure. In easier terms, compliance shows how easily the lungs expand to accommodate a given volume of air -Also called elastic work -It accounts for about 65% of the work of breathing -Compliance work can be calculated from: ∆V x ∆P/2 {∆V (increase in volume), ∆P (decrease in pressure)}

Answer 57

-static compliance -dynamic compliance

Answer 58

Static compliance is the compliance measured under static conditions, i.e. by measuring pressure and volume when breathing does not take place. Static compliance is the pressure required to overcome the elastic resistance of respiratory system for a given tidal volume under zero flow (static) condition.

Answer 59

Dynamic compliance is the compliance measured during dynamic conditions, i.e. during breathing.

Answer 60

stiff lungs

Answer 61

It is the work required to overcome the viscosity (resistance to a change in form or shape) of the lungs and chest wall structures Also called viscous resistance, it accounts for about 7% the work of breathing

Answer 62

It is the work required to overcome airway resistance during the movement of air into the lungs It accounts for about 25% of the work of breathing

Answer 63

additional work. It is the work required to expand and contract the thoracic cage

Answer 64

It is the work required to expand and contract the thoracic cage

Answer 65

The 3 (compliance, tissue resistance, airway resistance) only concern the lungs and NOT the thoracic cage, while the additional work concerns the thoracic cage

Answer 66

2X. -The compliance of the total lung-thorax system is only slightly more than half that of the lungs alone -Thus, almost two times as much energy is required for normal expansion and contraction of the total lung-thorax system as for expansion of the lungs alone

Answer 67

this is because not only do the lungs expand and contract, but the chest wall and other muscles involved in respiration also move to allow air to enter and exit the lungs.

Answer 68

During heavy breathing when air must flow through the respiratory passage at high velocity, the greater proportion of the work of breathing is used to overcome AIRWAY RESISTANCE

Answer 69

compliance and tissue resistance

Answer 70

airway resistance

Answer 71

No work is done in expiration (normal quiet breathing), however in deep breathing, or when airway resistance and tissue resistance are great, expiratory work does occur and could even become greater than inspiratory work -In asthma, airway resistance is increased many fold during expiration but much less so during inspiration

Answer 72

-During normal quiet breathing, only 3 - 4% of total energy expended by the body is required to energize the pulmonary ventilatory process -But during exercise (esp heavy exercise), the amount of energy required can increase by as much as 50-fold (esp in persons with any degree of increased airway resistance or reduced pulmonary compliance)

Answer 73

the person’s ability to provide enough muscle energy for the respiratory process alone

Answer 74

Compliance can also be defined as the change in lung volume as a function of change in the transpulmonary pressure (difference between Palv and the Pip) This means, a given Ptp will cause greater or lesser expansion depending on the compliance of the lungs

Answer 75

200ml/cmH2O (ie 0.2L/cmH2O)' This means every time the Transpulmonary pressure increases by 1cm of H2O, the lungs expand by 200ml

Answer 76

This means every time the Ptp increases by 1cm of H2O, the lungs expand by 200ml

Answer 77

Compliance can be determined by using the Oesophageal balloon (clinical method for measuring pleural pressure) which will give the Intrapleural pressure

Answer 78

Intrapleural pressure

Answer 79

check the book man.

Answer 80

2.3L or 2300mL

Answer 81

👉Lung Volume; FRC (functional residual capacity, about 2.3L or 2300ml) = ERV + RV is the amount of air that remains in the lungs at the end of normal expiration, FRC affects volume of distribution. Compliance reduces with less lung filling 👉Posture; lung volumes are usually reduced in supine position due to increase in intrathoracic blood volume. Compliance reduces in the supine position due to this reduction in lung volumes 👉Lung diseases; Compliance increases in emphysema (excess air in the lungs, its both obstructive and destructive, and mostly a consequence of long-term smoking) and reduces in fibrosis (which cause loss of elasticity of lung tissue) 👉Thoracic cage disease like Kyphoscoliosis (a musculoskeletal disorder in which there is an abnormal curvature of the spine in both the coronal and sagittal plane, results in under-ventilation of the lungs, and pulmonary hypertension) reduces compliance 👉Alveolar Surface Tension; a very important factor which affects (i.e. it resists distension) the compliance of the lungs is alveolar surface tension

Answer 82

FRC (functional residual capacity, about 2.3L or 2300ml) = ERV + RV is the amount of air that remains in the lungs at the end of normal expiration, FRC affects volume of distribution

Answer 83

The law of LaPlace describes this; the pressure created is directly promotional to the surface tension and inversely promotional to the radius of the alveolus P = 2 x T / R P (pressure, also known as collapse pressure) T (surface tension) r (radius of alveolus)

Answer 84

the pressure in a smaller alveolus would be greater than that in a larger alveolus if the surface tension is the same in both

Answer 85

-A very important factor affecting (i.e. it resists distension) the compliance of the lungs is surface tension that is exerted by fluid in the alveoli -Although the alveoli is relatively dry, it contains a very thin film of fluid -Surface tension is created because H2O molecules at the surface are attracted more to other H2O molecules than to air -Because whenever water forms a surface with air, the water molecules on the surface of the water have an extra strong attraction for one another -As a result, the surface water molecules are pulled tightly together by attractive forces from underneath. -The surface tension of an alveolus produces a force that is directed inwards, and as a result creates pressure within the alveolus

Answer 86

H2O molecules at the surface are attracted more to other H2O molecules than to air. Because whenever water forms a surface with air, the water molecules on the surface of the water have an extra strong attraction for one another

Answer 87

-Reduction of surface tension; thus increasing the compliance of the lungs and reducing work of breathing -Increases the alveolar radius by filling irregularities in the alveolar surface thus reducing the transpulmonary pressure. This effect increases compliance and reduces the work of breathing -Surfactant enhances alveoli stability

Answer 88

Surfactant is a surface active agent (in that when it spreads over the surface of a fluid, it greatly reduces surface tension), produced by the type II pneumocytes. It is a complex mixture of -phospholipids (dipalmitoylphosphatidylcholine [DPPC], also called dipalmitoyl lecithin), -protein (surfactant apoprotein) -ions (calcium ions, e.t.c)

Answer 89

-They don’t dissolve in the fluid, instead, they spread over its surface because one portion of each phospholipid molecule is hydrophilic and dissolves in the water lining the alveoli -Whereas the lipid portion of the molecule is hydrophobic and oriented towards the air, forming a lipid hydrophobic surface exposed to the air -The surface thus formed has between 1/12 to 1/2 the surface tension of a pure water surface

Answer 90

in their absence, the DPPC spreads so slowly over the fluid surface that it cannot function effectively

Answer 91

5-30 (increasing as surface increases)

Answer 92

It is the sum total of processes that must occur for air to enter the lungs from the atmosphere, and for air to leave the lungs into the atmosphere, as a result of pressure change in lung volume.

Answer 93

-Surfactant does not normally begin to be secreted into the alveoli until between the 6th and 7th month of gestation and in some babies even later than that -Thus, many premature babies have little or no surfactant in their alveoli, and so the lungs of this babies have extreme collapse tendencies, and this causes their alveoli to collapse -This condition is called respiratory distress syndrome (RDS) -It does not occur in all premature babies because the rate of development of the lungs depends on hormonal conditions (esp. thyroxine and hydrocortisone) and genetic factors -RDS is fatal if not treated immediately with strong measures (properly applied continuous positive pressure breathing) -Infants with RDS have inadequate gas exchange

Answer 94

properly applied continuous positive pressure breathing

Answer 95

It does not occur in all premature babies because the rate of development of the lungs depends on -hormonal conditions (esp. thyroxine and hydrocortisone) and -genetic factors

Answer 96

Respiratory distress syndrome Atelectasis

Answer 97

Atelectasis refers to partial or complete collapse of lungs, (in an entire lobe, or in an entire lung ). When a large portion of lung is collapsed, the partial pressure of oxygen is reduced in blood, leading to decreased partial pressure of oxygen, leading to dyspnea (shortness of breath).

Answer 98

1. Deficiency or inactivation of surfactant. It causes collapse of lungs due to increased surface tension, which leads to respiratory distress syndrome. 2. Obstruction of a bronchus or a bronchiole. In this condition, the alveoli attached to the bronchus or bronchiole are collapsed. 3. Presence of air (pneumothorax), fluid (hydrothorax), blood (hemothorax) or pus (pyothorax) in the pleural space.

Answer 99

asthma is the respiratory disease characterized by difficult breathing with wheezing. Wheezing refers to whistling type of respiration. It is due to bronchiolar constriction, caused by contraction of smooth muscles in bronchioles, leading to obstruction of air passage. Obstruction is further exaggerated by the edema of mucus membrane and accumulation of mucus in the lumen of bronchioles. Carbon dioxide accumulates, resulting in acidosis, dyspnea and cyanosis.

Answer 100

1. Inflammation of air passage: Leukotrienes released from eosinophils and mast cells during inflammation cause bronchospasm. 2. Hypersensitivity of afferent glossopharyngeal and vagal ending in larynx and afferent trigeminal endings in nose: Hypersensitivity of these nerve endings is produced by some allergic substances like foreign proteins. 3. Pulmonary edema and congestion of lungs caused by left ventricular failure: Asthma developed due to this condition is called cardiac asthma.

Answer 101

i. Tidal volume ii. Vital capacity iii. Forced expiratory volume in 1 second (FEV1) iv. Alveolar ventilation v. Partial pressure of oxygen in blood.

Answer 102

Emphysema is a type of chronic obstructive pulmonary disease (COPD) that affects the lungs. It is characterized by damage to the air sacs (alveoli) in the lungs, which causes them to lose their elasticity and become enlarged. This reduces the surface area available for gas exchange and makes it difficult to breathe. -Emphysema is most commonly caused by long-term exposure to cigarette smoke or other irritants, and is often associated with chronic bronchitis. -Symptoms of emphysema include shortness of breath, wheezing, coughing, and chest tightness. -Treatment may include medications, oxygen therapy, and lifestyle changes such as quitting smoking.

Answer 103

1. Cigarette smoking 2. Exposure to oxidant gases 3. Untreated bronchitis

Answer 104

shortness of breath, wheezing, coughing, and chest tightness.

Answer 105

medications, oxygen therapy, and lifestyle changes such as quitting smoking.

Answer 106

It's one of the primary Pulmonary Function Tests (PFT) used to check the health of the lungs and respiratory passageways.

Answer 107

When a spirometry test is performed, the subject breathes through a mechanical or electronic airflow sensor called a spirometer.

Answer 108

Mechanical Electrical

Answer 109

normal values for an -individual’s height, -weight, -sex, and -age.

Answer 110

blockage in one or more of the airways (an obstructive disorder),

Answer 111

inability to fully expand the lungs (a restrictive disorder).

Answer 112

4 volumes and 4 capacities

Answer 113

it equals the maximum volume to which the lungs can be expanded

Answer 114

the amount of air that can be inhaled and exhaled during one normal (quiet) breathing cycle (about 500 ml for men & women).

Answer 115

500mL in both male and female

Answer 116

Inspiratory reserve volume

Answer 117

Expiratory reserve volume

Answer 118

the amount of air that can be forcibly inhaled beyond a tidal inhalation (about 3,000 ml for men & 2,000 ml for women).

Answer 119

about 3,000 ml for men & 2,000 ml for women

Answer 120

the amount of air that can be forcibly exhaled beyond a tidal exhalation (about 1100 ml for men & 700 ml for women).

Answer 121

About 1100 ml for men & 700 ml for women

Answer 122

the amount of air remaining in the lungs after an ERV (most forced expiration) (= about 1,200 ml in men & women).

Answer 123

the harder it is for your lungs to breathe in and hold air.

Answer 124

our body and cells also receive less oxygen, forcing our heart to work harder to pump oxygen throughout the body

Answer 125

2 or more respiratory volumes added together

Answer 126

Tidal volume (Vt) + Inspiratory reserve volume (IRV)

Answer 127

About 3,500 mL, is the amount of air a person can breath in, beginning at the normal expiratory level and distending(outwardly expanding) the lungs to the maximum amount

Answer 128

Expiratory reserve volume (ERV) + Reserve volume (RV)

Answer 129

About 2,300 mL, is the amount of air remaining in the lungs after a normal expiration

Answer 130

Tidal volume(Vt) + Inspiratory reserve volume (IRV) + Expiratory reserve volume (ERV)

Answer 131

-About 4,600 mL, is the total amount of air a person can expel from the lungs after first filling the lungs to their maximum extent -It is approximately 80 percent of TLC. -The value varies according to age and body size.

Answer 132

-age -body size

Answer 133

Residual volume (RV) + Vital capacity (VC). OR Tidal volume (Vt) + Inspiratory reserve volume (IRV) + Expiratory reserve volume (ERV) + Residual volume (RV)

Answer 134

-All pulmonary volumes and capacities are usually about 20 to 25% less in women than in men, and - they are greater in large and athletic people than in small and asthenic people

Answer 135

Check the book.

Answer 136

Some air breathed doesn’t reach the gas exchange areas, but fills respiratory passages where gas exchange don’t occur (nose, pharynx, trachea)

Answer 137

On occasion, some of the alveoli are nonfunctional or only partially functional because of absent or poor blood flow (poor perfusion) through the adjacent pulmonary capillaries.

Answer 138

Dead space

Answer 139

-Anatomical dead space is the total volume of the conducting airways from the nose or mouth down to the terminal bronchioles, its about 150ml on the average. -It can also be described as the portion of the tidal volume that does not take part in gas exchange

Answer 140

-Physiological dead space is when alveolar dead space is included in the total measurement of dead space -Physiological dead space includes the anatomical dead space and alveoli which are well ventilated but poorly perfused, and are thus less efficient at exchanging gas with the blood

Answer 141

Normally (in healthy individuals), anatomical and physiological dead spaces are nearly equal because all the alveoli are functional in the normal lung

Answer 142

But in a person with partially functional or nonfunctional alveoli in some parts of the lungs, the physiological dead space may be as much as 10 times the volume of the anatomical dead space (1L – 2L).

Answer 143

in a person with partially functional or nonfunctional alveoli in some parts of the lungs, the physiological dead space may be as much as 10 times the volume of the anatomical dead space (1L – 2L).

Answer 144

High rates of air exchange in functioning alveoli --> that is higher alveolar ventilation, would bring in fresh oxygen-rich air and efflux carbon dioxide-laden air rapidly; --> consequently, the concentration of oxygen would be higher and the --> concentration of carbon dioxide would be lower within alveoli.

Answer 145

low rates of air exchange in functioning alveoli, ---> that is lower alveolar ventilation, would bring in fresh oxygen-rich air and efflux carbon-dioxide-laden air slowly; ---> consequently, the concentration of oxygen would be lower and ---> the concentration of carbon dioxide would be higher within the alveolus.

Answer 146

- The total volume of new air that enters the alveoli (tidal volume) and adjacent gas exchange areas each minute. -It equals the respiratory rate times the amount of new air that enters these areas per minute

Answer 147

VA = Freq x (VT – VD) VA (volume of alveolar ventilation per minute) VT (tidal volume) VD (physiological dead space volume) Freq (frequency of respiration per minute ie respiratory rate) VA = 12 x (500 – 150) = 4200ml/min

Answer 148

4200ml/min

Answer 149

alveolar ventilation