19: Respiratory System

Front 1

Respiration

Back 1

is the entire process of exchanging gases between the atmosphere & body cells

Front 2

Respiration consists of

Back 2

ventilation, external respiration, transport of gases by the blood between lungs & body cells, internal respiration, & cellular respiration

Front 3

External respiration

Back 3

is the exchange of gases between the air in the lungs & the blood

Front 4

Respiration

Back 4

is the entire process of exchanging gases between the atmosphere & body cells

Front 5

Respiration consists of

Back 5

ventilation, external respiration, transport of gases by the blood between lungs & body cells, internal respiration, & cellular respiration

Front 6

Ventilation

Back 6

is the movement of air in & out of the lungs

Front 7

External respiration

Back 7

is the exchange of gases between the air in the lungs & the blood

Front 8

Internal respiration

Back 8

is the exchange of gases between the blood & the body cells

Front 9

Cellular respiration

Back 9

is oxygen utilization & production of carbon dioxide in body cells.

Front 10

Respiration enables cells to

Back 10

harness the energy held in chemical bonds of nutrient molecules

Front 11

Without oxygen as a final electron acceptor

Back 11

much energy remains locked in nutrients

Front 12

A metabolic waste of respiration is

Back 12

carbon dioxide

Front 13

Carbon dioxide, when it reacts with water, forms

Back 13

carbonic acid which contributes to the pH of blood

Front 14

Too much carbon dioxide will

Back 14

lower blood pH

Front 15

Cellular respiration & control of blood pH explain why

Back 15

we must obtain oxygen & get rid of carbon dioxide.

Front 16

The upper respiratory tract includes

Back 16

nose, nasal cavity, sinuses, & pharynx.

Front 17

The lower respiratory tract includes

Back 17

larynx, trachea, bronchial tree, & lungs

Front 18

The nose is supported internally by

Back 18

muscle, bone, & cartilage

Front 19

Nostrils are openings through

Back 19

which air can enter & leave the nasal cavity

Front 20

Internal hairs of nostrils

Back 20

prevent entry of large particles carried in air.

Front 21

The nasal cavity is

Back 21

a hollow space behind the nose

Front 22

The nasal septum is a structure that

Back 22

divides the nasal cavity into left & right halves

Front 23

The nasal cavity is separated

Back 23

from the cranial cavity by the cribiform plate of the ethmoid bone & from the oral cavity by the hard palate

Front 24

Nasal conchae

Back 24

are located on the lateral walls of the nasal cavity & divide the nasal cavity into superior, inferior, & middle meatus’

Front 25

Nasal conchae function

Back 25

to support the mucous membranes that line the nasal cavity & to increase the surface area of the nasal cavity

Front 26

The lining of the upper portion of the nasal cavity contains

Back 26

olfactory receptors

Front 27

Most of the nasal cavity conducts air to & from

Back 27

the nasopharynx

Front 28

The mucous membrane lining the nasal cavity contains

Back 28

pseudostratified ciliated epithelium that is rich in mucous

Hint 28

secreting goblet cells

Front 29

The functions of the mucous membrane of the nasal cavity are

Back 29

to warm the air, to moisten the air, & to trap small particles entering the nasal cavity

Front 30

Cilia of the nasal cavity function

Back 30

to move mucous & any entrapped particles toward the pharynx.

Front 31

Sinuses are air filled spaces located

Back 31

within the maxillary, frontal, ethmoid, & sphenoid bones of the skull

Front 32

The functions of sinuses

Back 32

are to reduce the weight of the skull & to serve as resonant chambers that affect the quality of the voice

Front 33

The pharynx is located

Back 33

posterior to the oral cavity & between the nasal cavity & the larynx

Front 34

Functions of the pharynx are

Back 34

to move food into the esophagus, to move air into the larynx, & to aid in the production of sound

Front 35

The larynx is

Back 35

an enlargement in the airway superior to the trachea & inferior to the pharynx

Front 36

The functions of the larynx are

Back 36

to move air into the trachea, prevent foreign objects from entering the trachea, & to house vocal cords

Front 37

The larynx is composed of

Back 37

a framework of muscles & cartilages bound by elastic tissue

Front 38

The cartilages of the larynx are

Back 38

thyroid, cricoid, & epiglottic.

Front 39

The thyroid cartilage is located

Back 39

just superior to the thyroid gland

Front 40

The cricoid cartilage is located

Back 40

inferior to the thyroid cartilage

Front 41

The epiglottic cartilage is located

Back 41

attached to the upper border of the thyroid cartilage

Front 42

The epiglottis is flaplike structure supported by

Back 42

the epiglottic cartilage

Front 43

The functions of the epiglottis are

Back 43

to prevent foods & liquids from entering the air passages & to allow air to pass into the trachea

Front 44

The arytenoid cartilages are located

Back 44

superior to & on either side of the cricoid cartilage.

Front 45

The corniculate cartilages are located

Back 45

attached to the tips of the arytenoid cartilages

Front 46

The arytenoids & corniculate cartilages

Back 46

are attachments sites for muscles that help regulate tension on the vocal cords during speech & aid in closing the larynx during swallowing

Front 47

The cuneiform cartilages are located

Back 47

between the epiglottic & arytenoid cartilages & function to stiffen soft tissue in this region

Front 48

False vocal cords are located

Back 48

inside the larynx & are composed of muscle tissue & connective tissue with a covering of mucous membrane

Front 49

The function of the false vocal cords

Back 49

is to help close the larynx during swallowing

Front 50

The true vocal cords are located

Back 50

inferior to the false vocal cords & are composed of elastic fibers

Front 51

The functions of the true vocal cords are

Back 51

to produce sounds of speech

Front 52

A higher pitch of the voice is produced by

Back 52

increasing tension on true vocal cords & a lower pitch is produced by decreasing the tension on the cords

Front 53

The loudness of a vocal sound depends

Back 53

on upon the force of air passing over the vocal cords

Front 54

The glottis is the opening between

Back 54

vocal cords

Front 55

The mucous membrane that lines the larynx

Back 55

continues to filter incoming air by entrapping particles & moving them toward the pharynx by ciliary action

Front 56

The trachea

Back 56

is a flexible cylindrical tube & is located anterior to the esophagus in the thoracic cavity

Front 57

The trachea splits into

Back 57

right & left bronchi

Front 58

The inner wall of the trachea is lined with

Back 58

a ciliated mucous membrane that contains many goblet cells

Front 59

The mucous membrane of the trachea functions

Back 59

to filter incoming air & to move entrapped particles upward into the pharynx where the mucous can be swallowed

Front 60

The wall of the trachea is composed of

Back 60

C shaped pieces of hyaline cartilage, smooth muscle, & connective tissues

Front 61

The cartilaginous rings of the trachea prevent

Back 61

the trachea from collapsing & blocking the airway

Front 62

The soft tissues that complete the rings in the back of the trachea allow

Back 62

the esophagus to expand as food moves through it on the way to the stomach

Front 63

A blocked trachea causes

Back 63

asphyxiation

Front 64

A tracheostomy

Back 64

is the production of a temporary hole in the trachea

Front 65

The bronchial tree consists of

Back 65

branched airways leading from the trachea to the microscopic air sacs in the lungs

Front 66

Primary bronchi

Back 66

are the first branches of the trachea

Front 67

The carina is a ridge of cartilage that

Back 67

separates the primary bronchi

Front 68

The structure of a bronchus

Back 68

is similar to that of the trachea except the C shaped cartilaginous rings are replaced with cartilaginous plates where the bronchus enters the lung

Front 69

Elastic fibers

Back 69

are scattered throughout the lungs

Front 70

The branches of the bronchial tree function

Back 70

to filter incoming air & distribute it to the alveoli in all parts of the lungs.

Front 71

The alveoli function

Back 71

to provide a large surface area of thin epithelial cells through which gas exchanges can occur

Front 72

Visceral pleura

Back 72

are serous membranes attached to the surfaces of the lungs

Front 73

Parietal pleura

Back 73

are serous membranes that line the thoracic cavity

Front 74

The pleural cavity is the potential space between

Back 74

the visceral pleura & parietal pleura

Front 75

The functions of serous fluid in the pleural cavity are

Back 75

to lubricate serous membranes, reduce friction during lung movements & hold pleural membranes together

Front 76

The lobes of the right lung are

Back 76

superior, middle, & inferior

Front 77

The lobes of the left lung are

Back 77

superior & inferior

Front 78

Lobules of the lungs are

Back 78

divisions of lung lobes

Front 79

Breathing or ventilation

Back 79

is the movement of air from outside the body into the bronchial tree & alveoli, followed by a reversal of this air movement. Inspiration

Hint 79

is inhalation, the force that moves air into the lungs is atmospheric pressure, If the pressure inside the lungs & alveoli decreases, outside air will flow into the airways.

Front 80

Expiration

Back 80

is exhalation

Front 81

The diaphragm

Back 81

is located just inferior to the lungs & is composed of skeletal muscle

Front 82

The nerves that stimulate the diaphragm are

Back 82

the phrenic nerves

Front 83

When the diaphragm contracts it

Back 83

moves inferiorly & the thoracic cavity enlarges

Front 84

When the thoracic cavity enlarges, the intra alveolar pressure

Back 84

decreases

Front 85

The action of external intercostal muscles is

Back 85

to raise the ribs & elevate the sternum, which increases the size of the thoracic cavity

Front 86

When intra alveolar pressure falls

Back 86

air is moved into the airways

Front 87

When intercostal muscles move the thoracic wall upward & outward

Back 87

the parietal pleura & visceral pleura move

Front 88

Surface tension

Back 88

is the attraction of certain molecules to each other

Front 89

Surfactant

Back 89

is located in alveolar spaces & functions to reduce the alveoli’s tendency to collapse

Front 90

If a person needs to take a deeper than normal breath

Back 90

the diaphragm & external intercostal muscles may contract to a greater extent

Front 91

Other muscles that can be used to enlarge the thoracic cavity are

Back 91

the pectoralis minors & sternocleidomastoids

Front 92

Compliance

Back 92

is the ease at which the lungs can expand as a result of pressure changes occurring during breathing

Front 93

In a normal lung, compliance decreases as lung volume increases because

Back 93

an inflated lung is more difficult to expand that a lung at rest

Front 94

Factors that lead to a decrease in lung compliance are

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conditions that obstruct air passages, destroy lung tissue, or impede lung expansion in other ways

Front 95

The forces responsible for normal expiration come from

Back 95

elastic recoil of lung tissues & from surface tension

Front 96

As the diaphragm & external intercostals muscles relax, the elastic tissues cause the lungs to

Back 96

recoil

Front 97

Air is forced out of respiratory passageways because

Back 97

intra alveolar pressure rises above atmospheric pressure

Front 98

Muscles that aid in a more forceful exhalation than normal are

Back 98

internal intercostal muscles & abdominal wall muscles

Front 99

Spirometry

Back 99

is the measure of air volumes

Front 100

A respiratory cycle is

Back 100

one inspiration plus the following expiration

Front 101

Tidal volume

Back 101

is the amount of air that enters of leaves during a respiratory cycle

Front 102

Inspiratory reserve volume

Back 102

is the additional quantity of air after the resting tidal volume that can enter the lungs

Front 103

Expiratory reserve volume

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is the additional quantity of air that can exit the lungs after a resting tidal volume

Front 104

Residual volume

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is the amount of air that remains in the lungs after a forceful expiration

Front 105

Vital capacity

Back 105

is maximum amount of air that can be exhaled after taking the deepest breath possible

Front 106

Inspiratory capacity

Back 106

is maximum volume of air that can be inhaled following exhalation of tidal volume

Front 107

Functional residual capacity

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is volume of air that remains in the lungs following exhalation of tidal volume

Front 108

Total lung capacity

Back 108

is total volume of air that the lungs can hold

Front 109

Anatomic dead space

Back 109

is the space in airways

Front 110

Alveolar dead space

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is space in alveoli that do not carry out gas exchange due to poor blood flow

Front 111

Physiologic dead space

Back 111

is anatomical dead space plus alveolar dead space

Front 112

A spirometer measures

Back 112

respiratory air volumes

Front 113

Respiratory volumes & capacities are used

Back 113

to evaluate the course of respiratory illnesses

Front 114

Minute ventilation

Back 114

is the amount of new atmospheric air that is moved into the respiratory passages each minute & equals the tidal volume multiplied by the breathing rate

Front 115

The volume of air that reaches alveoli is calculated by

Back 115

subtracting the physiologic dead space from the tidal volume

Front 116

Alveolar ventilation rate

Back 116

is the volume of air that reaches alveoli multiplied by breathing rate & is a major factor affecting the concentrations of oxygen & carbon dioxide in alveoli

Front 117

Nonrespiratory air movements

Back 117

are air movements that occur in addition to breathing

Front 118

Examples of nonrespiratory air movements are

Back 118

coughing, sneezing, crying & laughing

Front 119

Nonrespiratory air movements usually result from

Back 119

reflexes

Front 120

Coughing involves

Back 120

taking a deep breath, closing the glottis, & forcing air upward from the lungs against the closure. Then the glottis is suddenly opened, & a blast of air is forced upward from the lower respiratory tract

Front 121

The function of a sneeze

Back 121

is to clear the upper respiratory passages Laughing involves

Hint 121

taking a deep breath & releasing it in a series of short expirations

Front 122

A hiccup

Back 122

is caused by sudden inspiration due to a spasmodic contraction of the diaphragm while the glottis is closed

Front 123

The function of a yawn

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may be rooted in primitive brainstem mechanisms that maintain alertness

Front 124

The respiratory center is composed of

Back 124

groups of neurons in the brainstem which controls breathing

Front 125

The functions of the respiratory center

Back 125

are to cause inhalation & exhalation, & to adjust the rate & depth of

Front 126

The components for the respiratory center are located widely scattered throughout the

Back 126

pons & medulla

Front 127

The medullary rhythmicity area includes

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two groups of neurons that extend throughout the length of the

Front 128

The dorsal respiratory group is important in

Back 128

stimulating the muscles of inspiration

Front 129

The ventral respiratory group is comprised of

Back 129

neurons that control other respiratory muscles

Front 130

Neurons of the pneumotaxic & apneustic center work together to

Back 130

inhibit inspiratory commands for the medulla & may contribute to the basic rhythm of breathing

Front 131

Partial pressure of a gas

Back 131

is amount of pressure each gas contributes

Front 132

Changes in blood pH are detected by

Back 132

central chemoreceptors.

Front 133

When carbon dioxide diffuses into the brain, it combines with water to form

Back 133

carbonic acid

Front 134

High concentrations of hydrogen ions in blood or cerebrospinal fluid are detected by

Back 134

central chemoreceptors

Front 135

In response to high hydrogen ion levels, the respiratory center triggers

Back 135

an increase in alveolar ventilation, which decreases hydrogen ions in blood

Front 136

Low concentrations of oxygen in blood are detected by

Back 136

peripheral chemoreceptors.

Front 137

When blood levels of oxygen are low

Back 137

ventilation increases & the concentration of oxygen in blood increases

Front 138

The inflation reflex helps regulate

Back 138

the depth of breathing

Front 139

The inflation reflex occurs when

Back 139

stretch receptors in the visceral pleura, bronchioles, & alveoli are stimulated as lung tissues are stretched

Front 140

The inflation reflex prevents

Back 140

overinflation of the lungs

Front 141

Hyperventilation

Back 141

is rapid & deep breathing & it lowers the blood concentration of carbon dioxide

Front 142

Alveoli

Back 142

are microscopic air sacs clustered at the distal ends of the finest respiratory tubes

Front 143

An alveolus consists of

Back 143

a tiny space surrounded by a thin wall that separates it from adjacent alveoli

Front 144

Alveolar pores are

Back 144

tiny openings in the walls of some alveoli

Front 145

Alveolar macrophages

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are phagocytic cells & function to destroy airborne agents that reach alveoli.

Front 146

The respiratory membrane is composed of

Back 146

two layers of epithelial cells & two basement membrane

Front 147

The respiratory membrane is the site of

Back 147

gas exchange between alveolar air & the blood.

Front 148

Molecules diffuse from regions where they are

Back 148

in higher concentration toward regions where they are in lower concentration.

Front 149

Carbon dioxide diffuses from

Back 149

blood in pulmonary capillaries to alveolar air

Front 150

CO2 diffuses from blood to alveolar air because

Back 150

the partial pressure of

Front 151

carbon dioxide

Back 151

is higher in the blood of pulmonary capillaries than in alveolar air

Front 152

Oxygen diffuses from

Back 152

alveolar air to blood in pulmonary capillaries because the partial pressure of oxygen is higher in alveolar air than in the blood of pulmonary capillaries

Front 153

Factors that affect diffusion across the respiratory membrane are

Back 153

surface area, distance, solubility of gases, partial pressure gradients, & diseases.

Front 154

Diseases that harm respiratory membranes are

Back 154

pneumonia and emphysema

Front 155

Breath analysis can detect alcohol in the blood because

Back 155

the respiratory membrane is so thin that alcohol can diffuse into alveolar air & be exhaled

Front 156

As oxygen & carbon dioxide enter blood, they dissolve

Back 156

in plasma or combine chemically with other atoms or molecules

Front 157

Almost all the oxygen carried in blood is bound to

Back 157

hemoglobin Hemoglobin consists of two types of components called heme & globin

Front 158

Each heme group contains an atom of

Back 158

iron

Front 159

Oxyhemoglobin

Back 159

is the combination of oxygen & hemoglobin

Front 160

Factors that promote the release of oxygen from hemoglobin are

Back 160

a decrease in the partial pressure of oxygen, increasing blood concentrations of carbon dioxide, acidity, & increased temperatures Blood flowing through capillaries gain carbon dioxide because the tissues have a high partial pressure of carbon dioxide

Front 161

Carbon dioxide is transported to lungs in one of the following three forms

Back 161

bound to hemoglobin, dissolved in plasma, or as bicarbonate ions.

Front 162

Hemoglobin can carry oxygen & carbon dioxide at the same time because

Back 162

they bind at different sites on hemoglobin

Front 163

Carbaminohemoglobin is the combination of

Back 163

carbon dioxide & hemoglobin

Front 164

The most important carbon dioxide transport mechanism involves the formation of

Back 164

bicarbonate ions

Front 165

Carbon dioxide forms _____ when it reacts with water

Back 165

carbonic acid

Front 166

Carbonic anhydrase

Back 166

is an enzyme that speeds up the reaction between carbon dioxide & water & is located inside red blood cells

Front 167

Carbonic acid dissociates into

Back 167

hydrogen ions & bicarbonate ions

Front 168

The chloride shift is

Back 168

the exchange of chloride ions & bicarbonate ions across the red blood cell membrane

Front 169

The chloride shift functions

Back 169

to maintain the ionic balance between the red blood cells & the plasma

Front 170

When blood reaches the pulmonary capillaries

Back 170

hydrogen ions & bicarbonate ions recombine to form carbonic acid

Front 171

In the pulmonary capillaries, carbonic acid becomes

Back 171

carbon dioxide & water

Front 172

In the lungs, carbon dioxide diffuses out of the blood until

Back 172

equilibrium is established between the partial pressure of carbon dioxide of the blood & that of the alveolar air.

Front 173

Life

Back 173

Span Changes

Front 174

Changes in the respiratory system over a lifetime reflect

Back 174

both the accumulation of environmental influences & the effects of aging in other organ systems.

Front 175

People who have been exposed to foul air are more likely to develop

Back 175

chronic bronchitis, emphysema, or lung cancer.

Front 176

The factors the change the ability of the respiratory system to clear pathogens from the lungs are

Back 176

a decreases in activity of cilia, thickening of mucus, & the slowing of swallowing, gagging & coughing reflexes.

Front 177

Factors that contribute to an overall increase in effort required to breathe are

Back 177

calcification of cartilage between the sternum & ribs & changes in skeletal structure of the thoracic cavity.

Front 178

The microscopic changes that occur in the lungs are

Back 178

expansion of alveolar walls, an increase in the amount of collagen, & a decreased amount of elastin.