A&P 400 (respiratory system) Flashcards

Question

WHY INFERIOR PORTION OF PHARYNX STRATIFIED SQUAMOUS????

Answer 1

B/c food passes here briefly

Answer 2

Lines the smaller bronchioles

Answer 3

trap pathogens, propel debris upward

Answer 4

macrophages

Answer 5

Forms gas exchange surfaces Distance between air and blood in capillaries is less than 1 µm

Answer 6

Respiratory mucosa lines nasal cavity through large bronchioles Pseudostratified ciliated columnar epithelium with mucous cells

Answer 7

underlying areolar tissue (LOOSE CT) ( underneath respiratory mucosa) supports respiratory epithelium mucous glands in trachea and bronchi

Answer 8

b/w the... Pseudostratified ciliated columnar epithelium with mucous cells

Answer 9

Flow of mucus/trapped debris (VIA CILIA) Sticky mucus produced by mucous cell and MUCOUS GLANDS Traps debris particles Moved by beating cilia

Answer 10

Swept toward pharynx Swallowed (to acids in stomach) or coughed out Epithelial stem cells replace damaged/old cells

Answer 11

Nose is primary route for air entering respiratory system

Answer 12

External nose is the portion you can see

Answer 13

Nostrils or external nares Paired openings into nasal cavity

Answer 14

Bony and cartilaginous structures make up the framework of the external nose

Answer 15

Dorsum of nose (bridge) formed by two nasal bones Maxilla and frontal bones also contribute

Answer 16

NASAL CARTILAGES: small, elastic cartilages extending laterally from bridge; help keep nostrils open I.e. Septal cartilage Lateral nasal cartilage Alar cartilage

Answer 17

superior border inferior border medial border lateral border

Answer 18

Superior border: ethmoid bone

Answer 19

Inferior border: hard palate, made of palatine bones and palatine process of maxillae

Answer 20

Medial border: nasal septum

Answer 21

Lateral border: ethmoid bone, maxillae, lacrimal bones, palatine bones, and inferior nasal conchae bones

Answer 22

Majority lined with respiratory mucosa

Answer 23

anteriorly merges with the external nares

Answer 24

posteriorly communicates with the NASOPHARYNX through the CHOANAE (AKA internal nares)

Answer 25

The term is a latinization from the Greek χοάνη, "choanē" meaning funnel. The choanae ( sg. : choana), posterior nasal apertures or internal nostrils are two openings found at the back of the nasal passage between the nasal cavity and the pharynx SINGULAR CHOANA

Answer 26

nasal vestibule lined with course hairs for filtering large dust particles " The area just inside the nostril (nose opening) that leads into the nasal cavity. The nasal vestibule is supported by the cartilage of the nose and is lined with tissue that contains short, coarse hairs."

Answer 27

Respiratory Region olfactory portion

Answer 28

Larger, inferior region of nasal cavity Lined w non-keratinized pseudostratified ciliated columnar epithelium with many goblet cells (respiratory mucosa)

Answer 29

Smaller, superior region of nasal cavity Olfactory receptors near superior nasal concha Have cilia, but no goblet cells

Answer 30

NON_KERATINIZED pseudostratified ciliated columnar epithelium (WITH MANY GOBLET CELLS) ---> I.e. respiratory mucosa

Answer 31

Nasal septum: Divides right and left nasal cavities

Answer 32

Septal cartilage Vomer Perpendicular plate of the ethmoid

Answer 33

Superior, middle, and inferior nasal conchae (bones) Superior, middle, and inferior nasal meatuses

Answer 34

Passages between nasal conchae Swirl incoming air to trap small particles Moves odorants to olfactory receptors Warms/humidifies air

Answer 35

Frontal, ethmoid, maxillary, and sphenoidal sinuses Open into nasal cavity

Answer 36

Mucus secreted by sinuses moisten nasal cavity Resonate sound Lighten skull

Answer 37

outgrowths of mucous membranes usually found around openings to paranasal sinuses (not necessarily normal? Can be symptomatic)

Answer 38

the LACRIMAL sac drains tears from the eyes the nasolacrimal duct carries tears from the lacrimal sac of the eye into the nasal cavityNw

Answer 39

Basal tears are in your eyes all the time to lubricate, nourish and protect your cornea. Basal tears act as a constant shield between the eye and the rest of the world, keeping dirt and debris away.

Answer 40

Reflex tears are formed when your eyes need to wash away harmful irritants, such as smoke, foreign bodies or onion fumes.

Answer 41

Emotional tears are produced in higher quantities than basal tears. They may be the same amount or more than reflex tears. Unlike, basal and reflex tears, emotional tears can be held back by the individual voluntarily, and they can stop when they want to.

Answer 42

We cry to protect our eyes, to wash out irritants and because, well, we are moved to tears. “There are three types of tears: basal tears, emotional tears and reflex tears,” explains David Silverstone, M.D., a professor of ophthalmology at the Yale School of Medicine.

Answer 43

Epiphora is the medical definition for having excess tears or watery eyes. It's caused by your eyes producing too many tears, or the tears in your eyes not draining away as they should.

Answer 44

The purpose of the nasolacrimal system is to drain tears from the ocular surface to the lacrimal sac and, ultimately, the nasal cavity.

Answer 45

EPIPHORA Blockage of the nasolacrimal system can cause tears to flow over the eyelid and down the cheek; this condition is epiphora.

Answer 46

late 16th century (in epiphora (sense 2)): via Latin from Greek epi ‘upon’ + pherein ‘to bear or carry’.

Answer 47

When you cry, tears come out of the tear glands under your eyelids and drain through the tear ducts that empty into your nose. Tears mix with mucus there and your nose runs. I.e. They go through the NasoLacrimal Ducts

Answer 48

your limbic system — the part of your brain that regulates emotions — sends a signal to your brain's message system to activate your lacrimal glands to produce tears.

Answer 49

Lamina propria (basement membrane) of nasal cavity has extensive network of vessels

Answer 50

Release heat to warm inhaled air Water from mucus evaporates to humidify inhaled air

Answer 51

Air moving from nasal cavity to lungs: ----> Heated to almost body temperature ----> Nearly saturated with water vapor

Answer 52

The reverse process occurs during exhalation ---> mucosa reabsorbs heat and water; reduces heat loss and water loss to environment ---> Releases air (with CO2) -- taking as much heat/water from released air as possible

Answer 53

Mouth breathing eliminates these benefits

Answer 54

Pharynx is shared by respiratory and digestive systems

Answer 55

Colloquially referred to as the throat

Answer 56

5 inch muscular tube from CHOANA (internal nares?) to cricoid cartilage

Answer 57

Lined with respiratory mucosa --> except oropharynx and hypopharynx (laryngopharynx) -- lined w/ stratified squamous

Answer 58

passage for food and air resonating chamber for speech lymphatic tissue (tonsil) to prevent the entry to the body ---> entry?? pathogens? ?

Answer 59

The tonsils are lymph nodes in the back of the mouth and top of the throat. They help to filter out bacteria and other germs to prevent infection in the body. A bacterial or viral infection can cause tonsillitis. Strep throat is a common cause.

Answer 60

1) Nasopharynx 2) Oropharynx 3) Laryngopharynx

Answer 61

superior part of the pharynx Lined with respiratory mucosa

Answer 62

non-keratinized stratified squamous epithelium

Answer 63

"The stratified squamous epithelium of the oropharynx is continuous with the laryngopharynx" "Anteriorly, the laryngopharynx opens into the larynx; whereas, posteriorly, it enters the esophagus."

Answer 64

From choanae to soft palate

Answer 65

Has pharyngeal openings of the auditory tubes (EUSTACHIAN tubes)

Answer 66

Contains adenoids (pharyngeal tonsils)

Answer 67

aden = gland oid

Answer 68

Adenoids are a patch of tissue that is high up in the throat, just behind the nose. They, along with the tonsils, are part of the lymphatic system. The lymphatic system clears away infection and keeps body fluids in balance. The adenoids and tonsils work by trapping germs coming in through the mouth and nose.

Answer 69

The Eustachian tube is named after the Italian anatomist Bartolomeo Eustachio (also spelled Eustachi and known by the Latin name Bartholomaeus Eustachius) who lived circa 1510-1574.

Answer 70

The primary function of the Eustachian tube is to equalize air pressure between the atmosphere and the middle ear. Yawning and swallowing cause contraction of the muscles connected to the Eustachian tube, enabling the tube to open to small amounts of air.

Answer 71

The equalizing of middle ear pressure is crucial to the proper workings of the eardrum. With equalized air pressure, the eardrum can vibrate appropriately and transmit sound.

Answer 72

middle part of the pharynx behind oral cavity Lined with non-keratinized stratified squamous epithelium

Answer 73

From soft palate to base of the epiglottis

Answer 74

The glottis opens into the windpipe and is responsible for the production of sound. While the epiglottis is a cartilaginous flap on top of the glottis that prevents the food from entering the larynx.

Answer 75

inferior part of the pharynx Lined with non-keratinized stratified squamous epithelium (NOTED ABOVE)

Answer 76

From epiglottis to cricoid cartilage

Answer 77

Cartilaginous tube that surrounds/protects glottis (“voice box”) Connects the pharynx with the trachea ---> Anterior to C4 – C6

Answer 78

laryngeal skeleton

Answer 79

1) Epiglottis 2) Thyroid Cartilage 3) Cricoid Cartilage

Answer 80

even though epiglottis and laryngopharynx are at the same level, they are different structures epiglottis itself is part of larynx however, the laryngopharynx is simply at the same level of the epiglottis

Answer 81

projects superior to glottis, forms lid over it During swallowing the larynx elevates, the epiglottis folds back over glottis, and blocks entry into respiratory tract

Answer 82

Prominent anterior surface is laryngeal prominence (Adam’s apple) Thyrohyoid ligament attaches it to hyoid bone; other ligaments attach it to epiglottis and smaller cartilages (e.g. cricoid)

Answer 83

shield shaped

Answer 84

Forms complete ring around larynx With thyroid cartilage, protects glottis and larynx provides attachment for laryngeal muscles/ligaments (muscles that control voice pitch, sound production, and so on)

Answer 85

ring-shaped

Answer 86

Cricoid cartilage (directly above ")

Answer 87

A tracheostomy is a surgically created hole (stoma) in your windpipe (trachea) that provides an alternative airway for breathing

Answer 88

The term “tracheotomy” refers to the procedure to make an incision (cut) into the trachea (windpipe). The temporary or permanent opening itself is called a “tracheostomy.” However, the terms are sometimes used interchangeably.

Answer 89

Medical conditions that make it necessary to use a breathing machine (ventilator) for an extended period, usually more than one or two weeks. Medical conditions that block or narrow your airway, such as vocal cord paralysis or throat cancer.

Answer 90

Arytenoid cartilages (2) Corniculate cartilages (2) (elastic cartilage) Cuneiform cartilages (2)

Answer 91

change position & tension of vocal cords via synovial joint w cricoid cartilage

Answer 92

support vocal folds and lateral epiglottis

Answer 93

where air passes through larynx

Answer 94

Made of VOCAL FOLDS and RIMA GLOTTIDIS (opening between folds) glottis= "the part of the larynx consisting of the vocal cords and the opening [Rima glottidis] between them. It affects voice modulation through expansion or contraction."

Answer 95

a long narrow opening, esp between the vocal cords and the cartilages at the back of the larynx. "Rima is Latin for a narrow cleft, crack or slit"

Answer 96

VOCAL FOLDS = tissue folds that contain vocal ligaments

Answer 97

Vibration of VOCAL FOLDS produce sound waves

Answer 98

Opened/closed by rotation of ARYTENOID cartilages

Answer 99

Phonation = sound production from larynx Vibration of vocal cords produces sound waves

Answer 100

modification of sounds by tongue, teeth, and lips

Answer 101

Amplification and resonance occur in pharynx, oral and nasal cavities, and paranasal sinuses

Answer 102

3 components: producing sound pitch volume

Answer 103

bands of elastic ligaments stretched between laryngeal cartilages muscles contract = cartilages move = pulls ligaments tight = stretched vocal folds out into airway = rima glottidis narrows = air passes through folds and they vibrate = sound

Answer 104

Depends on tension of vocal folds  taut = rapid vibration = pitch Androgens = thicker & longer vocal folds = lower pitch

Answer 105

Depends on the pressure of air

Answer 106

late Middle English: from Latin ventriculus, diminutive of venter ‘belly’. late Middle English: from Latin venter, ventr- ‘belly’ + -al.

Answer 107

The ventricular folds, also known as the vestibular or false vocal folds are located above the true vocal folds and separated from them by the laryngeal ventricle They are commonly referred as “false” vocal folds as they historically have been thought not to be directly involved in the production of “normal” voice.

Answer 108

aka false vocal cords above true vocal cords Space between = RIMA VESTIBULI Useful for holding breath against thoracic cavity pressure

Answer 109

depends on location: 1) superior to vocal fold = non-keratinized stratified squamous epithelium (RECALL, UP TO CRICOID, LARYNGOPHARYNX IS STRATIFIED SQUAMOUS) 2) inferior to vocal fold = pseudostratified ciliated columnar epithelium with goblet cells (respiratory mucosa)

Answer 110

Trachea ---> Main Bronchi ---> Lobar Bronchi ---> Segmental Bronchi ---> Bronchioles ---> Terminal bronchioles to pulmonary lobules

Answer 111

The trachea, bronchi, and bronchial branches convey air to and from lung gas exchange surfaces

Answer 112

Starts at C6 and ends at T5 by branching into bronchi 5 inches long 1 inch in diameter

Answer 113

Lies in front of the esophagus

Answer 114

Has 15–20 C-shaped tracheal cartilages

Answer 115

Prevent collapse and overexpansion allow esophagus to expand slightly into tracheal space

Answer 116

The hyaline cartilage in the tracheal wall provides support and keeps the trachea from collapsing. The posterior soft tissue allows for expansion of the esophagus, which is immediately posterior to the trachea.

Answer 117

ridge at the base of the trachea that separates the openings of the right and left main bronchi

Answer 118

a cartilage situated at the point where the trachea (windpipe) divides into the two bronchi. etymology: "keel"

Answer 119

highly innervated mucosa very sensitive cough reflex to prevent choking ---> prevent food/debris reaching bronchi

Answer 120

ELASTIC LIGAMENTS as well as, TRACHEALIS (muscle)

Answer 121

Contraction of trachealis narrows trachea; restricts airflow

Answer 122

Trachealis = how why? Tracheal diameter changes often, mostly controlled by sympathetic stimulation which increases airflow

Answer 123

Tracheal cartilages are incomplete posteriorly allowing for expansion when swallowing

Answer 124

mucosa sub-mucosa fibromuscular membrane adventitia

Answer 125

pseudostratified ciliated columnar epithelium with goblet cells (respiratory mucosa)

Answer 126

loose CT with seromucous glands

Answer 127

release a mixture of mucus and antibacterial compounds. This mixture also serves to humidify and warm the air before it gets to the lungs.

Answer 128

allow tracheal diameter change during inhalation/exhalation

Answer 129

binds trachea to other organs

Answer 130

First division of bronchi Right and left bronchus go into each lung

Answer 131

(Due to position of heart) Right bronchus wider, at a steeper angle, and shorter than left = foreign objects in trachea often go into it

Answer 132

"The left lung has to accommodate the heart, which is positioned slightly towards the left side of the thoracic cavity. This anatomical arrangement causes the left bronchus to be more horizontal and curved to navigate around the heart."

Answer 133

Have complete cartilaginous rings

Answer 134

Lined with respiratory mucosa

Answer 135

one goes to each lobe of the lung (5 FIVE lobar bronchi) ---> 3 lobes on right ---> 2 lobes on left (superior, middle, inferior lobes on right) (superior, inferior lobes on left)

Answer 136

Smooth muscle encircles lumen and increasingly replaces cartilage

Answer 137

Also lined with respiratory mucosa

Answer 138

Each lung has approximately 10 segmental bronchi

Answer 139

Each one supplies triangular shaped unit of lung (BRONCHOPULMONARY segment)

Answer 140

divisions of each LOBE "A bronchopulmonary segment is a portion of lung supplied by a specific segmental bronchus and its vessels" "These arteries branch from the pulmonary and bronchial arteries, and run together through the center of the segment." "Veins and lymphatic vessels drain along the edges of the segment."

Answer 141

No cartilage; thick smooth muscle

Answer 142

A layer of hyaline cartilage supporting the tracheal rings surrounds the submucosa. The hyaline cartilage layer is sturdy but flexible and prevents the collapse of the trachea during expiration.

Answer 143

Ciliated simple columnar epithelium w goblet cells & Ciliated simple cuboidal epithelium w/o goblet cells (club cells or Clara cells) recall: simple cuboidal/columnar lines smaller bronchioles

Answer 144

Club cells, also known as bronchiolar exocrine cells,[1] are low columnar/cuboidal cells with short microvilli, found in the small airways (bronchioles) of the lungs.[2] They were formerly known as Clara cells.

Answer 145

Sympathetic nervous system (NE/E) causes bronchodilation ---> increases airflow

Answer 146

Parasympathetic nervous system causes bronchoconstriction ---> Decreases airflow ---> Histamine, asthma attack, allergies

Answer 147

Extreme bronchoconstriction can occur during allergic reactions such as ASTHMA

Answer 148

3 lobes (right lung) + 2 lobes (left lung) = 5 lobes right primary bronchus = steep, wider, shorter left primary bronchus = angled, narrower, longer (angled and longer to get around heart, narrower b/c less space) In general, each lung has 10 segments (TEN BRONCHOPULMONARY SEGMENTS) Internally, each lobe further subdivides into hundreds of lobules.

Answer 149

Bronchioles open into short segments called terminal bronchioles, which are thin-walled branches of the bronchioles. Terminal bronchioles transition into respiratory bronchioles.

Answer 150

(SAME AS bronchioles) ---> ciliated columnar cells and club cells (also known as Clara cells) ___NOTE THAT CLASS NOTES SAY THAT TERMINAL BRONCHI HAVE ***NON-CILIATED*** cells --> macrophage action instead

Answer 151

Terminal bronchioles lead to PULMONARY LOBULES (for gas exchange)

Answer 152

one main bronchus per lung 2 + 3 lobar bronchi per lobe 10 segmental bronchi (on each side) per BRONCHOPULMONARY segment then many terminal/respiratory bronchioles PER lobule

Answer 153

Many terminal bronchioles Each terminal/respiratory bronchiole supplies a pulmonary lobule Smooth muscle (no cartilage) = airway patency vulnerable to muscle spasms

Answer 154

Non-ciliated simple columnar epithelium macrophages remove debris (no cilia to move mucous)

Answer 155

Many, many respiratory bronchioles Simple cuboidal & simple squamous epithelium ---> AGAIN DIFFERENT FROM ABOVE (follow classnotes)

Answer 156

First place where external respiration can occur, although limited

Answer 157

Internal respiration occurs in the body tissues, where cells release carbon dioxide and take in oxygen from the blood. External respiration occurs in the lungs or gills and occurs when the body takes in oxygen from the atmosphere and releases carbon dioxide.

Answer 158

Trachea: larynx to main bronchi in mediastinum Main bronchi: one to each lung; cartilage rings are complete Lobar bronchi: 3 in right lung, 2 in left; one per lobe Segmental bronchi: branch to give rise to bronchioles (one per bronchopulmonary segment) Bronchioles Terminal bronchioles Respiratory bronchioles

Answer 159

Structural Division: Upper Respiratory Tract vs. Lower Respiratory Tract * Functional Division: Conducting Region vs. Respiratory Region

Answer 160

nose, nasal cavity & pharynx

Answer 161

larynx, trachea, bronchi & lungs

Answer 162

nose, pharynx, larynx, trachea, bronchi, bronchioles, & terminal bronchioles

Answer 163

respiratory bronchioles, alveolar ducts, alveolar sacs, & alveoli

Answer 164

Right lung (3): superior lobe, middle lobe, inferior lobe Left lung (2): superior lobe and inferior lobe (Each lobe has multiple bronchopulmonary segments) ---> 10 on right? ---> 9 on left?

Answer 165

Right lung is slightly shorter d/t liver Left lung is 10% smaller d/t heart

Answer 166

DEEP FISSURES Each lung is cone shaped and divided into lobes by deep fissures

Answer 167

Right lung horizontal fissure between superior/middle lobes; oblique fissure between middle/inferior lobes

Answer 168

oblique fissure between superior/inferior lobes

Answer 169

Apex (tip) extends to superior border of first rib Concave base rests on diaphragm Cardiac notch—left lung; accommodates pericardium/heart

Answer 170

dense connective tissue; fixes positions of bronchi, major nerves, blood vessels, and lymphatics CONTAINS HILUM (?)

Answer 171

medial depression on each lung Allows passage of main bronchus, pulmonary vessels, nerves, lymphatics

Answer 172

‘little thing, trifle’ "a depression or fissure where structures such as blood vessels and nerves enter an organ"

Answer 173

Grooves on surface of lungs mark positions of great vessels

Answer 174

Visceral pleura Parietal pleura

Answer 175

serous membrane sacs surrounding the lungs

Answer 176

covers outer surfaces of lungs

Answer 177

covers inner surface of thoracic wall; extends over diaphragm and mediastinum

Answer 178

potential space between visceral and parietal layers of pleural sac Contains pleural fluid that reduces friction of the lungs against the wall

Answer 179

Pneumothorax Hemothorax Hydrothorax Empyema

Answer 180

pleural cavity fills with air common cause is chest trauma

Answer 181

pleural cavity fills with blood

Answer 182

collection of serous fluid m/c cause is cardiac failure

Answer 183

pericardial effusion ---> cardiac tamponade (?) pleural effusion ---> hydrothorax

Answer 184

em = in puon = pus Pus in the pleural cavity m/c cause is pneumonia

Answer 185

Any may cause partial or complete lung collapse = Pneumothorax Hemothorax Hydrothorax Empyema

Answer 186

"A collapsed lung occurs when air escapes from the lung. The air then fills the space outside of the lung between the lung and chest wall. This buildup of air puts pressure on the lung, so it cannot expand as much as it normally does when you take a breath. The medical name of this condition is pneumothorax."

Answer 187

A terminal bronchiole Venule, arteriole, lymphatics, capillaries Multiple alveolar sacs

Answer 188

Pulmonary lobules are wrapped in elastic CT (expand and return to original size when filled with air)

Answer 189

Each terminal bronchiole branches into multiple respiratory bronchioles

Answer 190

alveolar ducts, which lead to alveolar sacs made of alveoli (sing. alveolus)

Answer 191

respiratory bronchioles and alveoli

Answer 192

~150 million alveoli (singular, alveolus) per lung; give lungs an open, spongy appearance Surrounded by extensive capillary network for gas exchange

Answer 193

Surrounded by elastic fibers—expansion/recoil aids air movement Each alveolar duct ends in clusters of alveoli (alveolar sacs, or alveolar saccules)

Answer 194

A primary pulmonary lobule is defined as the lung unit distal to the respiratory bronchioles. It is significantly smaller than an acinus, and is composed of alveolar ducts, alveolar sacs and alveoli.

Answer 195

Type 1 Pneumocytes Type 2 Pneumocytes Roaming alveolar macrophages

Answer 196

simple squamous epithelium thin, delicate, sites of gas diffusion

Answer 197

produce surfactant: oily secretion; reduces surface tension of water in alveoli to prevent collapse

Answer 198

locate and phagocytize particles that could clog the alveoli

Answer 199

where gas exchange occurs between blood and alveolar air aka alveolar–capillary membrane or respiratory membrane

Answer 200

1) Alveolar cell layer (epithelium) 2) Fused basement membranes (alveolar and capillary) 3) Capillary endothelium

Answer 201

Minimal distance separating air and blood (average ~0.5 µm) allows for rapid diffusion Large total surface area (70 - 100 m2 ) also allows for a large amount of diffusion

Answer 202

air movement in/out of lungs Maintains ALVEOLAR VENTILATION --> air movement in/out of alveoli

Answer 203

Two integrated processes: EXTERNAL respiration and INTERNAL respiration

Answer 204

exchange of gases between blood, lungs, and external environment gas diffusion occurs across BLOOD AIR BARRIER between alveolar air and alveolar capillaries

Answer 205

occurs between blood and tissues Absorption of oxygen from blood into tissues Release of carbon dioxide by tissue cells into blood

Answer 206

Respiration and ventilation are two different things. Ventilation is mechanical and involves the movement of air. Respiration is physiologic and involves the exchange of gases in the alveoli (external respiration) and in the cells (internal respiration).

Answer 207

Abnormalities affecting external respiration affect gas concentrations in interstitial fluids and cellular activities

Answer 208

Hypoxia = low tissue oxygen levels Severely limits metabolic activities

Answer 209

Anoxia = no oxygen supply Much of damage caused by heart attacks and strokes is the result of localized anoxia

Answer 210

Molecules in a gas bounce around independently When contained, collisions with container wall cause pressure More collisions = higher pressure

Answer 211

Boyle's law = More collisions occur when molecules are in smaller container = Pressure is inversely related to volume (P = 1/V) I.e. Decreased volume = more collisions = higher pressure Increased volume = less collisions = lower pressure

Answer 212

diffusion: the net movement of molecules from an area of greater concentration to an area of lesser concentration I.e. Molecules move down their concentration gradient ** Likeiwse with pressure: ---> Gases will move from an area of high pressure to low pressure ---> Gases will move down their pressure gradient

Answer 213

Atmospheric pressure and intrapulmonary pressure Atmospheric pressure is the pressure of air around us Intrapulmonary pressure is the pressure inside respiratory tract, usually measured at the alveoli

Answer 214

Pulmonary ventilation involves changing volume of the thoracic cavity

Answer 215

Movements of the DIAPHRAGM and RIB CAGE (E.g. levator costarum) ---> change the volume of the thoracic cavity, which expands or compresses the lungs (changes lung volume) Change in volume = change in pressure (Boyle’s Law)

Answer 216

Start of a breath During inhalation During exhalation (Volume and Pressure Changes During Pulmonary Ventilation)

Answer 217

Pressures inside and outside thorax are identical; no air movement Expanding thoracic cavity expands lungs: (DIAPHRAGM contracts, increases space in lungs --> also note action of levator costarum and other mm.)

Answer 218

Parietal pleura attached to thoracic wall; visceral pleura to lungs Pleural fluid forms bond between layers d/t surface tension

Answer 219

Thoracic cavity enlarges Increased volume causes decreased pressure Pressure inside lungs drops below atmospheric pressure (Poutside > Pinside) Air moves into lungs from an area of high pressure to low pressure

Answer 220

Thoracic cavity decreases in volume Decreased volume causes increased pressure Pressure inside lungs increases above atmospheric pressure (Poutside < Pinside) Air is forced out of the lungs from an area of high pressure to low pressure

Answer 221

negative Negative intrapulmonary pressure pulls air into lungs ---> Intrapulmonary pressure < atmospheric pressure

Answer 222

POSITIVE Positive intrapulmonary pressure pushes air out of lungs Intrapulmonary pressure > atmospheric pressure

Answer 223

May be involved with inhalation (inspiratory muscles) or exhalation (expiratory muscles

Answer 224

quiet or forced

Answer 225

Quiet breathing is normal breathing

Answer 226

Forced breathing is laboured breathing

Answer 227

Active inhalation via primary inspiratory muscles Passive exhalation via elastic recoil of tissues, not by muscle action

Answer 228

Force breathing requires accessory respiratory muscles I.e. requires contribution from all repsiratory muscles (?) --> also, exhalation is no longer passive

Answer 229

primary vs accessory inspiratory uscles

Answer 230

Primary inspiratory muscles used for quiet inhalation

Answer 231

used for forced inhalation

Answer 232

Diaphragm external intercostals

Answer 233

Diaphragm does ~75 % of movement ---> Flattens floor of thoracic cavity External intercostals do ~25 % of movement ---> elevate ribs and pull out

Answer 234

Sternocleidomastoid Scalenes Pectoralis minor Serratus anterior

Answer 235

Increase speed/amount of rib movement to move more air when needed (tissue oxygen demands not met by primary inspiratory muscles) In other words, when you are very active, your regular "QUIET" inspiration is not providing adequate oxygen to tissue ---> forced inhalation is required to create greater speed/amount of rib movement to generate greater pressure difference, to let more air into the lungs, more quickly

Answer 236

There are no primary ("quiet") expiratory muscles Quiet exhalation is a passive process done by elastic recoil

Answer 237

Diaphragm relaxes ---> dome moves superiorly External intercostals relax ---> ribs move down Passive elastic recoil caused by: ---> stretched elastic fibres ---> inward pull of surface tension from alveolar fluid (??)

Answer 238

Internal intercostals ---> depress ribs (?) transversus thoracis ---> depress ribs (?) external oblique, internal oblique, rectus abdominis

Answer 239

Abdominal muscles push diaphragm upward ---> possibly via decreased abdominal cavity volume pushing organs against diaphragm (?) Decrease thoracic cavity volume quickly Allow greater pressure change and faster airflow out of lungs

Answer 240

Surface Tension Compliance Airway Resistance

Answer 241

Water molecules attracted to each other more strongly than to air molecules ---> "this is why soap bubbles collapse inward and burst" (?) Thin layer of alveolar fluid coats luminal surface of alveoli ---> Responsible for 2/3 of elastic recoil of lungs ---> Must be overcome during each inhalation Surfactant (from type 2 pneumocytes) ---> reduces surface tension below simple water

Answer 242

Surfactant (from type 2 pneumocytes)

Answer 243

Surfactant is not produced until 24th – 28th week of development

Answer 244

Recall: premature infants have decreased surfactant = ^ surface tension = alveoli collapse = great effort to open alveoli with each inhalation This leads to something called RDS (respiratory distress syndrome)

Answer 245

Tx: intubation, ventilation, artificial surfactant

Answer 246

Compliance = the ability of the lungs and chest wall to expand

Answer 247

lungs & chest wall expands easily elastic stretches easily and elastic recoil is not strong making exhalation more difficult Seen with some OBSTRUCTIVE LUNG DISEASES ---> Like EMPHYSEMA

Answer 248

Compliance is increased in obstructive lung disease like pulmonary emphysema, less in asthma and at a minor degree in chronic bronchitis. In emphysema, the elastic recoil is decreased (as a result of increased compliance -- or rather, decreased elastic recoil CAUSES increased compliance) and the P-V curve is shifted up and left. This is due to the loss of elastic tissue as a result of alveolar wall destruction.

Answer 249

lungs & chest wall difficult to expand This is restrictive lung disease --> Pulmonary fibrosis (asbestosis, TB, etc.) --> Pneumothorax --> Pleural effusion --> Chest wall injury or trauma --> Scoliosis --> Respiratory distress syndrome (RDS) --> Obesity and pregnancy

Answer 250

Restrictive lung diseases - fibrosis and interstitial lung disease: In interstitial lung diseases, the lung and/or chest wall compliance has become decreased. Therefore there is an increased tendency for the lungs to collapse.

Answer 251

decreased elastic recoil means that air is no exiting as effectively --> I.e. it is obstructing continued passage/cycling of air

Answer 252

low compliance means there is restriction of tissue to even let air in to begin with. In other words, even if recoil mechanism is intact in itself, the fibrosed tissue of lungs simply don't expand to begin with

Answer 253

the resistance of the respiratory tract to airflow during inhalation and exhalation

Answer 254

d/t pressures: ---> Bronchioles expand during inhalation = decreased resistance ---> Bronchioles narrow during exhalation = increased resistance

Answer 255

Obstructive lung diseases E.g. Asthma Chronic Obstructive Pulmonary Disease (COPD) ---> Chronic bronchitis ---> Emphysema

Answer 256

Restrictive lung diseases include diseases that make it hard for the lungs to expand and fill with air (low compliance)

Answer 257

Obstructive lung diseases include disease that make it hard for people to expel air from the lungs (increased resistance) ---> increased airway resistance ---> increased compliance / reduced recoil ** EXTRA: WHY DOES COPD (e.g. chronic bronchitis) INCREASE AIRWAY RESISTANCE? ---> Expiratory flow limitation is a key characteristic in chronic obstructive pulmonary disease (COPD). Increased airway resistance occurs due to bronchoconstriction, destruction of elastic tissue in the airways, and mucus hypersecretion from goblet cells caused by irritation of the epithelium. --- ALSO: "More severe degrees of emphysema resulted in a marked increase in total airway resistance due almost entirely to the increase in the peripheral airway component." (?????)

Answer 258

Chronic Obstructive Pulmonary Disease (COPD) E.g. -> Chronic bronchitis -> Emphysema Asthma

Answer 259

Pulmonary fibrosis (asbestosis, TB, etc.) Pneumothorax Pleural effusion Chest wall injury or trauma Scoliosis Respiratory distress syndrome (RDS) Obesity and pregnancy

Answer 260

COPD (Chronic bronchitis, Emphysema) Asthma

Answer 261

General term for progressive disorder of the airways that restricts airflow and reduces alveolar ventilation

Answer 262

Chronic bronchitis + Emphysema

Answer 263

Long-term inflammation and swelling of bronchial lining; leads to overproduction of mucus Frequent cough, lots of sputum can clog airways, increasing resistance, reduced efficiency ---> INCREASED AIRWAY RESISTANCE Cigarette smoking most common cause ---> Also other environmental irritants

Answer 264

Chronic, progressive condition Alveolar walls are damaged ---> Loss of elastic tissues increases compliance Loss of respiratory surface area restricts oxygen absorption (shortness of breath, intolerance of physical exertion Strongly linked with CIGARETTE smoking

Answer 265

emphysema increases 2) COMPLIANCE chronic bronchitis 3) INCREASES AIRWAY RESISTANCE ---> both contribute to the OBSTRUCTIVE nature of the lung disease

Answer 266

aka asthma bronchitis Characterized by conducting passageways that are extremely sensitive to irritation Airways respond by constricting smooth muscles along bronchial tree, edema/swelling of mucosa, increased mucus Breathing difficult; resistance markedly increased

Answer 267

Triggers include allergies, toxins, exercise

Answer 268

normal variation in breathing rate and depth (12 to 18 breaths per minute)

Answer 269

temporal cessation of breath (sleep apnea) a- -pnoe

Answer 270

painful, difficult, or laboured breathing (shortness of breath, SOB)

Answer 271

rapid breathing rate (> 20 breaths per minute)

Answer 272

Bradypnea is a symptom in which your breathing rate is lower than expected for your age and activity level.

Answer 273

upward & outward movement of chest during contraction of intercostals

Answer 274

abdomen moving outward when contracting diaphragm (b/c contraction of diaphragm reduces volume of abdominal cavity while increasing volume of thoracic cavity

Answer 275

deep inspiration, closure of rima glottidis & strong expiration blasts air out to clear respiratory passages

Answer 276

muscles of expiration spasmodically contract, pushing air out of nose and mouth

Answer 277

spasmodic contraction of diaphragm & quick closure of rima glottidis produce sharp inspiratory sound

Answer 278

significant amount of inhaled air followed by quick exhalation

Answer 279

forced expiration against closed rima glottidis (increases abdominal pressure)

Answer 280

many convulsive inhalations (where rima glottidis prematurely closes, letting in only a little air) & a long exhalation

Answer 281

SPIROMETER spiro- = breath

Answer 282

spirogram What is Spirogram? Spirogram is the graphical record of lung capacities and lung volumes using a spirometer.

Answer 283

males taller people younger people

Answer 284

tidal volume inspiratory reserve volume expiratory reserve volume residual volume minimal volume

Answer 285

Amount of air moved in or out of lungs during single respiratory cycle at rest (normal quiet breathing) Averages 500 mL

Answer 286

70% reaches respiratory zone for external respiration (350ml) 30-35% remains in conducting airways = anatomic (respiratory) dead space (150ml)

Answer 287

Dead space is the volume of air that is inhaled that does not take part in the gas exchange, because it either remains in the conducting airways or reaches alveoli that are not perfused or poorly perfused. It means that not all the air in each breath is available for the exchange of oxygen and carbon dioxide.

Answer 288

Amount of air you can breathe in beyond tidal volume (with forced inspiration)

Answer 289

Amount of air you can exhale beyond tidal volume (after normal (quiet?) exhalation) (forced exhalation (?))

Answer 290

Amount of air left in lungs after maximal exhalation (1200 mL) presumably after forced exhalation

Answer 291

Amount of air in the lungs if they were allowed to collapse Included in residual volume Cannot be measured in a healthy person --> collapsed lung is medical emergency

Answer 292

Lung capacities cannot be measured directly but are calculated by taking sum of various respiratory volumes

Answer 293

inspiratory capacity vital capacity functional residual capacity total lung capacity

Answer 294

VT + IRV tidal volume + inspiratory reserve volume ---> I.e. volume of air with forced INHALATION "Amount of air you can inhale after normal exhalation" (??)

Answer 295

ERV + VT + IRV expiratory reserve volume + tidal volume + inspiratory reserve volume I.e. "Maximum amount of air you can move in or out of lungs per cycle"

Answer 296

ERV + residual volume I.e. Amount of air remaining in lungs after complete quiet cycle

Answer 297

Vital capacity + residual volume Total volume of lungs

Answer 298

Averages 6000 mL in adult males, 4200 mL in adult females

Answer 299

Pulmonary function tests (PFT) measure volume, capacities, and rates of flow

Answer 300

measures how much air you can forcibly exhale after taking a deep breath

Answer 301

This is the amount of air expired during the first, second, and third seconds of the FVC test (FEV1, FEV2, FEV3)

Answer 302

This is the average rate of flow during the middle half of the FVC test

Answer 303

This is the fastest rate that you can force air out of your lungs

Answer 304

All aspects of respiratory function decrease with age As elastic tissue deteriorates, vital capacity decreases Arthritis stiffens rib joints, reducing compliance and maximum respiratory minute volume

Answer 305

Some degree of (features of) emphysema is normal for people over age 50 Extent varies widely with exposure to cigarette smoke and other irritants Respiratory function declines more with more years of smoking

Answer 306

aggressive class of malignancies Derived from epithelial cells in conducting passages, mucous glands, alveoli

Answer 307

Signs/symptoms often not present until tumors restrict airflow or compress adjacent structures ---> Chest pain, shortness of breath, cough/wheeze, weight loss

Answer 308

lung cancer Causes more deaths per year than any other type of cancer

Answer 309

85–90 percent of lung cancer cases are direct result of cigarette smoking

Answer 310

Cigarette smoke contains several carcinogens (cancer-causing agents)

Answer 311

Mucus and cilia in normal respiratory epithelium clean inhaled air

Answer 312

Irritants/carcinogens in smoke cause progressive series of changes in the epithelium

Answer 313

Cells damaged, and functional characteristics change Cilia damaged and paralyzed—causes local buildup of mucus Epithelium becomes less effective at protecting deeper, delicate parts of respiratory tract

Answer 314

Tissue changes structure Stressed respiratory surface converts to stratified epithelium ---> Protects underlying layers but not deeper parts of tract ---> May be reversed if stimulus is removed before further damage

Answer 315

Neoplasia: Growth of abnormal cells forms a cancerous tumor (neoplasm) Anaplasia: most dangerous stage ---> loss of differentiation/specialization of cells ---> Cells become malignant and metastasize to other parts of body

Answer 316

principles that govern the movement and diffusion of gas molecules

Answer 317

(P1V1=P2V2) Pressure and volume have an inverse relationship determines direction of air movement during pulmonary ventilation

Answer 318

the atmosphere

Answer 319

Partial pressure (P) = pressure exerted by single gas in a mixture

Answer 320

All the partial pressures of gases added together equal the total pressure exerted by the gas mixture

Answer 321

also applies to gas in the respiratory tract

Answer 322

LOCATION ( in respiratory tract) Gas mixture inside respiratory tract varies by location

Answer 323

Inhaled air gets moistened and warmed

Answer 324

In alveoli, it mixes with air remaining from previous breath

Answer 325

Exhaled air mixes with air in anatomic dead space

Answer 326

As gas mixture varies, so do the partial pressures of its component gases

Answer 327

At a given temperature, the amount of a particular gas in solution is directly proportional to the partial pressure of that gas above the liquid (*Also dependent on the solubility that gas in the solution) "Henry's law is a gas law that states that the amount of dissolved gas in a liquid is directly proportional to its partial pressure above the liquid." *** HENRY'S LAW AND BREATHING: "The main application of Henry's law in respiratory physiology is to predict how gasses will dissolve in the alveoli and bloodstream during gas exchange. The amount of oxygen that dissolves into the bloodstream is directly proportional to the partial pressure of oxygen in alveolar air."

Answer 328

Blood arriving in pulmonary capillaries has lower PO2 and higher PCO2 than in alveolar air ---> Oxygen has been used in the tissues ---> Carbon dioxide has been created in the tissues and released in the blood

Answer 329

Increases blood PO2 (oxygen enters blood) Decreases PCO2 (carbon dioxide leaves blood)

Answer 330

The actual exchange of gases occurs due to simple diffusion. "Gas exchange during respiration occurs primarily through diffusion. Diffusion is a process in which transport is driven by a concentration gradient. Gas molecules move from a region of high concentration to a region of low concentration."

Answer 331

PO2 of blood leaving lungs in pulmonary veins DROPS SLIGHTLY***** when it mixes with blood from capillaries around conducting passageways; still higher than PO2 of interstitial fluid Oxygen diffuses to interstitial fluid

Answer 332

PCO2 higher in tissues/interstitial fluid than in blood Carbon dioxide diffuses from tissues into blood

Answer 333

cellular respiration = using oxygen inside the cell to create ATP

Answer 334

~20 mL oxygen

Answer 335

Only ~0.3 mL (1.5 percent) is dissolved in the plasma

Answer 336

is bound to IRON IONS in heme units of hemoglobin (Hb)

Answer 337

globular proteins

Answer 338

with one heme unit

Answer 339

4 heme units 4 molecules of O2

Answer 340

a bright red substance formed by the combination of hemoglobin with oxygen, present in oxygenated blood.

Answer 341

Carbon monoxide (CO) is dangerous because it also bind to heme units, making them unavailable for O2 transport ---> HIGHER AFFINITY FOR HEME UNITS ---> harder to get off

Answer 342

Percentage of heme units containing bound oxygen at any moment

Answer 343

graph showing hemoglobin saturation at different partial pressures of oxygen

Answer 344

Shape reflects hemoglobin’s increased affinity for oxygen with each oxygen molecule bound ---> Increases steeply until it plateaus near saturation ---> Hemoglobin is > 90 percent saturated with oxygen when PO2 is above 60 mm Hg

Answer 345

~97 % saturated PO2 is 95 mm Hg

Answer 346

Hemoglobin in blood leaving body tissues is ~75 % saturated PO2 is 40 mm Hg

Answer 347

Hemoglobin in blood in active muscle is only ~20 % saturated Large amounts of oxygen being released to tissue PO2 is only ~15–20 mm Hg

Answer 348

measured to determine respiratory function measured using a PULSE OXIMETER

Answer 349

an oximeter that measures the proportion of oxygenated hemoglobin in the blood in pulsating vessels ********************************Ie>>>>>>>>> ARTERIES, especially the capillaries of the finger or ear.

Answer 350

An ideal hemoglobin saturation or SpO2 is between 96% and 99% ---> recall this measurement is from arteries ---> not veins

Answer 351

An SpO2 of 90-95% requires investigation An SpO2 of 80-89% requires urgent medical treatment An SpO2 of < 80% is potentially fatal

Answer 352

Serum Pressure = Sp

Answer 353

A shift in the curve represents a change in the affinity for O2 a shift to the right (red curve) means oxygen is being more easily released from hemoglobin a shift to the right (blue curve) means oxygen is more tightly bound to hemoglobin

Answer 354

1) pH changes 2) temperature changes 3) changes in the partial pressure of CO2 (PCO2) 4) changes in the concentration of 2,3-bisphosphoglycerate (B P G)

Answer 355

via BOHR EFFECT

Answer 356

H+ binds to hemoglobin & alters it, decreasing the Hb affinity for O2 pH decreases (ACIDIC): saturation curve shifts to the right (lower affinity) pH increases (BASIC): saturation curve shifts to the left (higher affinity)

Answer 357

Higher temperature leads Hb to release oxygen more readily (lower affinity) Especially important in active tissues (generate heat)

Answer 358

Increased PCO2 will shift the curve to the right (DECREASED AFFINITY)

Answer 359

recall that increase in CO2 causes decrease in pH ---> both subsequently LOWER the affinity for O2

Answer 360

I.e. INCREASE in metabolism ==== INCREASE in temperature (e.g. exercise) + increase in CO2 ---> DECREASE in pH ALL = DECREASE IN O2 AFFINITY

Answer 361

slightly different structure compared to adult Hb

Answer 362

It has a higher affinity for O2 (a left shift)

Answer 363

This higher affinity allow fetal RBCs to pull more oxygen from the mother as it binds it more strongly

Answer 364

Carries up to 30% more oxygen compared to adult hemoglobin

Answer 365

Has a higher affinity for Hb than O2 (200x higher than O2) Therefore, even small concentrations of CO decreases O2 carrying capacity

Answer 366

headache, dizziness, weakness, nausea, vomiting, chest pain, confusion

Answer 367

in peripheral tissues

Answer 368

Carbon dioxide is generated by AEROBIC metabolism

Answer 369

needs to be transported to the lungs for removal

Answer 370

1) Dissolved in plasma (~7 %, limited solubility in plasma) 2) Bound to hemoglobin in RBCs (~23 %) ---> Resulting compound is carbaminohemoglobin (HbCO2) 3) Converted to bicarbonate ion, HCO3− (~70 %)

Answer 371

This carbaminohemoglobin is formed by the reaction between carbon dioxide and an amino (-NH2) residue from the globin molecule, a compound of hemoglobin and carbon dioxide, and is one of the forms in which carbon dioxide exists in the blood.

Answer 372

Converted to bicarbonate ion, HCO3− (~70 %)

Answer 373

(in response to rise in pH) CO2 + H2O ----> H2CO3 (hydrogen donor = acid) ----> H+ + HCO3- ----> HCO3- goes to kidneys *** (in response to fall in pH) HCO3- + H+ ----> H2CO3 ----> CO2 + H2O ----> CO2 goes to lungs

Answer 374

Most carbon dioxide entering blood (~70 %) converts to carbonic acid (then Bicarbonate ion)

Answer 375

CARBONIC ANHYDRASE

Answer 376

Carbonic anhydrases (CAs) catalyze a reaction fundamental for life: the bidirectional conversion of carbon dioxide (CO2) and water (H2O) into bicarbonate (HCO3−) and protons (H+)

Answer 377

anhydrous + -ase

Answer 378

dissociates into bicarbonate and hydrogen ions H2CO3 ↔ HCO3– + H+

Answer 379

Bicarbonate ions (HCO3–) exchanged (leave cell) for an extracellular chloride ion (Cl–)

Answer 380

Hydrogen ion (H+) binds to Hb, forming HbH+ Why (?) ---> Hb molecules function as pH buffers

Answer 381

PROCESS WHERE Bicarbonate ions (HCO3–) exchanged (leave cell) for an extracellular chloride ion (Cl–)

Answer 382

pissed out if excessive As long as renal function is maintained, excess bicarbonate is excreted in the urine fairly rapidly.

Answer 383

H+ binds to Hb ---> HbH+ (Hb acting as a pH buffer) HCO3- leaves cell via CHLORIDE SHIFT (Chloride ion enters RBC, HCO3- leaves cell) ---> pissed out if excess

Answer 384

Deoxygenation of blood increases its ability to carry CO2 Conversely, oxygenated blood has a reduced capacity to carry CO2 This helps RBCs exchange CO2 for O2 in the lungs (external respiration) and exchange O2 for CO2 in the tissues (internal respiration)

Answer 385

The Haldane effect is a property of hemoglobin first described by John Scott Haldane, within which oxygenation of blood in the lungs displaces carbon dioxide from hemoglobin, increasing the removal of carbon dioxide. Consequently, oxygenated blood has a reduced affinity for carbon dioxide.

Answer 386

1) CO2 diffuses into bloodtream 2) 93% diffuses into RBC 3) 7% DISSOLVES in plasma 4) of the 93%, 23% binds to Hb (CARBAMINOHEMOGLOBIN = HbCO2) 5) the remaining 70% converted to CARBONIC ACID --- via Carbonic anhydrase 6) the carbonic acid dissociates into H+ & bicarbonate ion (HCO3-) --- This is done via bicarbonate buffer pathway 7) the H+ then binds to Hb (Hb acts as pH buffer) 8) the HCO3- leaves RBC (in exchange for Chloride ion entering) --- done via process called CHLORIDE SHIFT 9) HCO3- is pissed out if excess

Answer 387

Chloride shift (also known as the Hamburger phenomenon or lineas phenomenon, named after Hartog Jakob Hamburger) is a process which occurs in a cardiovascular system and refers to the exchange of bicarbonate (HCO3−) and chloride (Cl−) across the membrane of red blood cells (RBCs).

Answer 388

1) Hb + O2 (from alveoli) 2) HCO3- ENTERS RBC (REVERSE reaction) ---> HCO3- + H+ ---> Carbonic acid (H2CO3) 3) H2CO3 ---> CO2 +H2O 4) thus, CO2 DIFFUSES to alveoli and out lungs ---> Note that this reverse process is best to counter-act drop in pH (bicarbonate BUFFER pathway) 5) ADDITIONALLY, the carbaminohemoglobin releases the CO2 ---> CO2 from HbCO2 is released out of lungs

Answer 389

Spontaneous rhythmic discharge of MEDULLARY NEURON is modified by neurons in the PONS

Answer 390

1) Dorsal respiratory group/inspiratory center (DRG) 2) Ventral respiratory group (VRG) 3) Pre-Botzinger Complex

Answer 391

1) apneustic centres 2) Pneumotaxic centres

Answer 392

a- (un) -pneustikos (breathing) pneumo- (lung/breath) -taxis (arrangement)

Answer 393

Most basic control

Answer 394

Pacemaker cells in medulla oblongata generate cycles of contractions in DIAPHRAGM

Answer 395

Paired respiratory rhythmicity centers establish pace of respiration by adjusting pacemaker cells and coordinating other respiratory muscles

Answer 396

Mainly concerned with inspiration Inspiratory center of DRG controls lower motor neurons to primary (QUIET) inspiratory muscles (external intercostals, diaphragm) ---> intercostal nn to external intercostals ---> phrenic nn to diaphragm During normal breathing, active for 2sec, inactive for 3sec

Answer 397

Dorsal respiratory group

Answer 398

During normal breathing, active for 2sec, inactive for 3sec

Answer 399

Dorsal respiratory group varies response through input from: ---> Chemoreceptors detecting O2, Co2, and pH (via CO2) levels in blood/CSF ---> Baroreceptors that detect pressure/stretch monitor stretch of lung wall

Answer 400

Mainly associated with forced breathing Functions only when breathing demands increase and accessory (SECONDARY) respiratory muscles are involved

Answer 401

the DRG ---> via feedback that indicates loss of homeostasis that DRG can not resolve on its own (?)

Answer 402

Rhythm maker that send input to DRG Essential to all forms of breathing but poorly understood

Answer 403

MUSCLES OF EXHALATION ---> (Accessory) ---> recall there are no primary exhalation mm

Answer 404

IT MODIFIES ****** (medulla nervous output) Transmit nerve impulses to the DRG Modifies the rhythm of breathing by adjusting nerve output from the medullary respiratory centers

Answer 405

1) APNEUSTIC CENTRE 2) PNEUMOTAXIC CENTRES

Answer 406

Promote inhalation by stimulating DRG

Answer 407

VAGUS NERVE Degree of stimulation adjusted based on sensory information from the vagus nerve about lung inflation

Answer 408

Inhibit apneustic centers Promote passive or active exhalation ---> opposite to apneustic centres

Answer 409

shortens inhalation duration (= faster respiratory rate)

Answer 410

INHIBITS INSP or SHORTENS INSP ---> faster respiration****

Answer 411

Decreased output slows pace and increases depth of respiration

Answer 412

faster breathing

Answer 413

slower breathing

Answer 414

1) Cerebral cortex (LANGUAGE, MEMORY, EMOTION, REASONING) 2) Hypothalamus (HUNGER/THIRST, SEX DRIVE, BP, TEMP, MOOD) 3) Limbic system (EMOTION, SEXUAL STIM, MEMORY) 4) Chemoreceptors 5) Baroreceptors (mechanoreceptors) 6) proprioceptors

Answer 415

voluntarily change or stop breathing to keep out gases or water

Answer 416

H2O + CO2 --> H2CO3 --> H+ & HCO3- increasing PCO2 & H+ in blood strongly stimulates DRG and sends impulses down nerves to resume breathing

Answer 417

phrenic nerve & intercostal nerves

Answer 418

if you hold your breath until you faint, you will then resume breathing (intercostal and phrenic nerve reflex)

Answer 419

Central and peripheral chemoreceptors detect chemical changes in the blood/CSF

Answer 420

Under normal conditions, PCO2 is the most important factor influencing respiration

Answer 421

Rise of only 10 percent in arterial PCO2 doubles respiratory rate

Answer 422

PO2 levels have to drop below 60 mm Hg before triggering respiratory centers

Answer 423

Central chemoreceptors located in the medulla oblongata of CNS

Answer 424

monitor PCO2 and H+ in cerebrospinal fluid

Answer 425

Peripheral chemoreceptors are a part of PNS ---> monitor PCO2, PO2, & H+ in blood

Answer 426

aortic bodies carotid bodies

Answer 427

aka aortic bodies in wall of aortic arch close to aortic baroreceptors

Answer 428

VAGUS NERVE (CNX)

Answer 429

aka carotid bodies ---> in wall of L/R common carotid arteries, close to carotid sinus baroreceptors

Answer 430

part of glossopharyngeal nerve (CN IX)

Answer 431

"too much" kapnos = "smoke" A slight increase in PCO2 (and thus H+) is called hypercapnia

Answer 432

hypoventiliation or obstructive diseases like COPD

Answer 433

stimulates central and peripheral chemoreceptors DRG activated, and hyperventilation occurs (rapid & deep breathing) ---> wasn't DRG only concerned with quiet breathing (????) ---> perhaps b/c DRG stimulates VRG (which activates accessory breathing muscles) ---> Helps expel excess CO2

Answer 434

A decrease in PCO2 (<40 mmHg) is called hypocapnia Most commonly caused by hyperventilation (eg. anxiety)

Answer 435

central & peripheral chemoreceptors not stimulated no impulses sent to DRG DRG sets its own pace until CO2 accumulates and PCO2 increased to 40 mmHg

Answer 436

A decrease in PO2 (100-50 mmHg) peripheral chemoreceptors stimulated DRG activated, inspiration occurs to bring in more O2

Answer 437

detect lung expansion with stretch receptors (baroreceptors) in walls of bronchi & bronchioles send inhibitory signal to DRG via vagus nerves (CN X) activated when tidal volume > 1500ml (remember, TV = 500mL at rest) ---> Called the Hering-Breuer reflex

Answer 438

Ventilation increases even before the need for O2 increases proprioceptors of joints and muscles activate DRG upper motor neurons in primary motor cortex also activate DRG

Answer 439

.. ___ Varies number of breaths/minute (respiratory rate) and volume moved per breath (tidal volume—VT) ___ Respiratory rate (f)= Number of breaths/minute Normal adult resting range: 12–18 breaths/minute Average for children: 18–20 breaths/minute ___ Respiratory minute volume (VE) = Volume of air moved per minute respiratory rate x tidal volume = RESPIRATORY MINUTE VOLUME ___ pulmonary perfusion increases ___ O2 diffusing capacity increased 3X the rate at rest (rate that O2 diffuses from alveolar air to blood) ---> d/t more pulmonary capillaries maximally perfused ___ 1) Proprioception 2) limbic anticipation 3) primary motor cortex ___ 1) decreased PO2 2) increased PCO2 3) increased temperature

A&P 400 (respiratory system) Flashcards

(499 cards)