(Lesson 19) Respiratory System Flashcards
1
Q
Respiratory System
A
Supplies the body’s trillions of cells with oxygen and disposes of CO2.
2
Q
Pumlonary Respiration
A
Air moved in and out of the lungs so gases in the air sacs (alveoli) of the lungs are continuously replaced.
AKA **Ventilation **or breathing
3
Q
External Respiration
A
Gas exchange must occur between the blood and air at the lung alveoli. Oxygen in the air sacs diffuses into the blood; CO2 in blood diffuses into air sacs.
4
Q
Transport of respiratory gases
A
Oxygen and CO2 must be transported between the lungs and the celld of the body. This is accomplished by the cardiovascular system with blood serving as the transporting fluid.
5
Q
Internal respiration
A
At the systemic capillaries, gases must be exchanged between blood and tissue cells.
6
Q
Cellular respiration
A
The process by which oxygen is used by the cells and CO2 is produced as a waste product during this chemical process that converts glucose to cellular energy (ATP)
7
Q
Organs of the respiratory system
A
- nose
- nasal cavity
- paranasal sinuses
- pharynx
- larynx
- bronchi and smaller branches
- lungs
- Alveoli
8
Q
Nose
A
the only externally visible part of the respiratory system.
- provides airway for respiration
- moisten and warms entering air
- filters inhaled air to cleanse it of foreign particles
- serves as a resonating chamber for speech
- houses olfactory receptors
9
Q
External nose
A
Consists of:
- frontal and nasal bones superiorly
- maxillary bones laterally
- flexible plates of hyaline cartilage inferiorly (lateral, septal, and alar cartilages)
10
Q
Nasal Cavity
A
lies in and posterior to the external nose.
- Nares
- posterior nasal apertures
- lined with ciliated pseudostratified columnar epithelium
- vestibule
- lined with 2 types of muscous membranes
- olfactory mucosa
- near the roof of the nasal cavity.
- Houses receptors for smell
- respiratory mucosa
- lines the majority of the nasal cavity
- olfactory mucosa
11
Q
External Nares
A
nostrils
12
Q
Posterior nasal apertures
A
AKA choanae/internal nares
connection between the nasal cavity and the nasopharynx
13
Q
Boundaries of nasal cavity
A
- roof is formed by ethmoid/sphenoid bones
- floor is formed by palate
- anteriorly, hard palate (palatine bone and palatine process of maxilla)
- posteriorly, muscular soft palate
14
Q
Vestibule
A
the part of the nasal cavity that lies just superior to the nostrils, within the flared wings of the external nose. “Porch, entranceway”
Lined with skin containing sebaceous glands, sweat glands and numerus hair follicles.
15
Q
Vibrissae
A
- Nose hairs
- filter large particles like insects and lint
16
Q
Respiratory Mucosa
A
- Pseudostratified ciliated columnar epithelium
- scattered goblet cells
- underlying connective tissue lamina propria w/ tubular alveolar glands
- mucous cells:
- secrete mucous
- Serous cells:
- secrete watery fluid containing digestive enzyme
- mucous cells:
17
Q
Nasal glands and goblet cells
(respiratory mucosa)
A
- Each day they secrete a quart of mucous contaning lysozyme.
- Lysozyme is an enzyme that digests and destroys bacteria
- sheet of mucous traps inhaled dust, bacteria, pollen, viruses, and other debris from the air.
- Cilia moves sheets of mucous to posterior pharynx where it swallowed and broken down by digestive juices in the stomach
18
Q
Nasal Mucousa
A
- Richly supplied with sensory nerve endings
- sneeze reflex is stimulated when irritating particles (dust, pollen) contact this sensitive mucosa.
19
Q
The nose in cold temperatures
A
Vascular plexus engorge with warm blood to be able to continue to heat incoming air. Because of the abundance and superficial location of these vessels, nose bleeds are often common and profuse.
20
Q
The Nasal Conchae
A
mucosa-covered scroll-like structures projecting medially from each lateral wall of the nasal cavity
- superior concha of ethmoid bone
- middle concha of ethmoid bone
- inferior concha (separate bone)
- *meatus: *groove inferior to each concha
Function:
- increased surface area traps particualte matter
- moisten/heat during inhalation
- reclaim moisture and heat during exhalation
21
Q
Paranasal sinus
A
- a ring of air-filled cavities surrounding the nasal cavity
- lined with same mucosa and perform same functions as nasal cavity.
- suctioning effect by nose blowing helps drain them
- located in
- frontal bone
- sphenoid bone
- ethmoid bone
- maxillary bone
22
Q
sinusitis
A
- inflammation of the paranasal sinuses
- caused by viral, bacterial, or fungal infections
- passages become blocked, vaccuum formed and sinus headache occurs
- if infection persists, inflammatory fluid exerts painful pressure
- Serious cases can be treated by promoting drainage and antibiotics
23
Q
Pharynx
A
- funnel-shaped passageway that connects the nasal cavity and mouth superiorly to the larynx and esophagus inferiorly
- descends from base of skull to 6th cervical vertebrae
- common passageway for food and air
- commonly called the throat
24
Q
Nasopharynx
A
- Directly posterior to nasal cavity
- serves only as air passageway
- soft palate and uvula prevent food from entering
25
Pharyngeal Tonsils
* Adenoids
* lymphoid organ tissue that destroys pathogens entering the nasopharynx in the air
26
pharyngotympanic (auditory) tube
* drains the middle ear
* opens into each lateral wall of nasopharynx
27
tubal tonsil
* a ridge of pharyngeal mucosa posterior to the pharyngotympanic tube
* provides the middle ear some protection against infections that may spread from pharynx
28
Oropharynx
* lies posterior to the oral cavity
* extends inferiorly from soft palate/uvula to epiglottis/hyoid bone
* air and food pass through
* stratified squamous epithelium
29
Fauces
* "throat"
* the archlike entranceway to the oropharynx directly behind the mouth
30
epithelium of the pharynx
* Nasopharynx: **Ciliated pseudostratified epithelium**
* Oropharynx: **protective stratified squamos epithelium**
* Laryngopharynx: **stratified squamos epithelium**
31
Palatine Tonsils
* paired lymph nodes
* lateral to the walls of the fauces
* oropharynx
32
Lingual tonsil
* unpaired
* covers the posterior surface of the tongue
* oropharynx
33
Laryngopharynx
* common passageway for air and food
* from hyoid to inferior border of cricoid
* directly posterior to the larynx and continous with:
* esophagus: conducts food and fluid to stomach
* larynx: conducts air to respiratory tract
34
Larynx
* Voice Box
* From 4th cervical vertebra to 6th cervical vertebra
* attaches to hyoid bone superiorly and opens into laryngopharynx
* inferiorly it is continuous with trachea
35
Functions of the Larynx
1. produces vocalizations
2. provides an open airway
3. acts as a switching mechanism to route air and food into the proper channels
* inlet (superior opening) is closed during swallowing and open during breathing
36
9 Cartilages of Larynx
1. Thyroid Cartilage
2. Cricoid Cartilage
3. Arytenoid Cartilages (2)
4. Corniculate Cartilages (2)
5. Cuneiform Cartilages (2)
6. Epiglottis
37
Thyroid Cartilage
(Larynx)
* large, shield-shaped cartilage formed by two cartilage plates
* Laryngeal prominence:
* Adam's Apple
* Larger in males than in females because males sex hormone stimulates its growth during puberty
38
Cricoid Cartilage
| (Larynx)
* The only laryngeal cartilage that forms a complete ring
* Shaped like a signet ring, wide posteriorly and narrow anteriorly
* perched atop the trachea
39
Arytenoid Cartilages
| (Larynx)
* Most important of paired larygeal cartilages
* anchor the vocal cords
40
Epiglottis
| (Larynx)
* Means "upon the tongue". "Guardian of the airways".
* composed of elastic cartilage and is almost entirely covered by a mucosa.
* stalk attaches anteriorly to the internal aspect of the angle of the thyroid cartilage
* projects superoposteriorly and attached to the posterior aspect of the tongue
* during swallowing the entire larynx is pulled superiorly and the epiglottis tips inferiorly to cover and seal the laryngeal inlet
41
Vocal folds
aka True vocal cords
* paired vocal ligaments that run anteriorly from the arytenoid cartilages to the thyroid cartilage.
* composed largely of elastic fibers
* covered in avascular mucus that make the folds look pearly white
42
Vocal Folds Function
* Air exhaled from lungs
* Folds vibrate in in a wave motion and clap together
* Basic sounds for speech are produced
43
Rima Glottidis
| (vocal folds)
* medial opening between the vocal folds through which air passes
44
glottis
* vocal folds and rima glottidis together form this
45
Vestibular Folds
AKA false vocal cords
* another pair of horizontal mucosal folds that lie directly superior to the vocal folds
* Play no part in sound production
* define a slit like cavity between them and the true vocal cords that enhance the high-frequency sounds (like the tweeter on stereo speakers)
46
Voice Production
* Pitch is determined by length and tension of vocal folds
* men have longer vocal folds that vibrate slower
* women have tense short vocal folds that vibrate quicker
* Loudness depends on the force with which air rushes across vocal folds
47
Laryngitis
* Inflammation of the larynx-vocal folds swell
* usually caused by infection from a bad cold
* swelling interferes with ability to vibrate, producing hoarseness
48
Valsalva's maneuver
* the abdominal muscles contract, glottis closes, and exhalation is prevented
* intrathoracic and intra-abdominal pressure increases
* these events evacuate the rectum, stabilize the trunk of the body when one lifts a heavy load
49
Trachea
* windpipe
* descends from larynx through the neck and into the mediastinum
* ends by dividing into two main bronchi
* early anatomists mistook the trachea for a rough-walled artery. (Trachea=rough)
50
Trachealis muscle
* Smooth muscle fibers in the open posterior parts of the cartilage rings
* Contraction decreases the diameter of traches
* helps expel irritants from trachea by accelerating the exhaled air speed to 100 mph (during coughing and sneezing)
51
Carina of trachea
* a ridge on the internal aspect of the last tracheal cartilage
* marks the point where the trachea branches into the *two main bronchi*
* mucosa that lines the carina is highly sensitive to irritants so cough reflex often originates here
52
Tracheal Wall
* Contains 16-20 C shaped rings formed by hyaline cartilage
* w/ intervening fibroelastic connective tissue
53
Microscopic structure of tracheal wall
* Consists of several layers
* mucous membrane
* submucosa
* adventitia
54
mucous membrane of tracheal wall
* consists of inner epithelium and lamina propria
* epithelium
* Air filtering (ciliated)
* pseudostratified columnar epithelium
* same epithelium that occurs throughout most of the respiratory tract
* Lamina propria
* contains many elastic fibers
* separated from the submucosa by a sheet of **elastin**
* ****Elastin enables trachea to stretch during inhalation and recoil during exhalation
55
Submucosa of tracheal wall
* connective tissue below mucosa
* contains glands with both serous and mucus cells
* *seromucous glands: *help produce sheets of mucus within trachea
56
Adventitia of tracheal wall
* The most external layer of tracheal wall
* connective tissue that contains tracheal cartilage
57
Bronchial Walls
* similar to trachea
* cartilaginous rings replaced by irregular plates of cartilage
* amount of smooth muscle increases significantly
58
Main Bronchi
* right and left main bronchi are also called *primary bronchi*
* the largest conduits in the bronchial tree
* branches of the trachea in the mediastinum
* lie directly posterior to the large pulmonary vessels that supply the lungs
* the right main bronchis is wider, shorter, and more vertical than the left
* an accidentally inhaled object is more likely to lodge in the right main bronchus
59
lobar bronchi
* secondary bronchi divisions after the main bronchi
* three on the right, two on the left
* divide into tertiary or *segmental bronchi*
60
segmental bronchi
* tertiary bronchi that are branches of the lobar bronchi
* divide repeatedly into smaller bronchi
* there are about 23 orders or air tubes in the lungs
61
bronchioles
* little bronchi
* tubes smaller than 1 mm in diameter
62
terminal bronchioles
* the smallest bronchioles
* less than .5mm in diameter
63
As bronchi tubes become smaller, these changes occur
* Supportive connective tissue changes
* cartilage diminishes, elastin remains
* Epithelium changes
* from pseudostratified columnsar to simple columnar and then to simple cuboidal epithelium in the terminal and respiratory bronchioles
* Smooth muscle becomes important
64
Alveoli
* air exchange chambers at the end of the respiratory tree
* about 300 million within the lungs
* account for most of the lung volume, providing tremendous surface area for gas exchange
* 40 times more surface area than the skin
65
Respiratory bronchioles
* The first respiratory zone structures which branch from the terminal bronchioles of the conducting zone
* scattered alveoli protrude from their walls
66
Alveolar ducts
* straight ducts whose walls consists almost entirely of alveoli
* derive from respiratory bronchioles
* lead to alveolar sacs
67
Alveolar Sacs
* terminal clusters of alveoli
* derive from alveolar ducts
* *alveoli and alveoli sacs are not the same things*
* like a bunch of grapes--individual grapes are alveoli
68
Atrium
* Opening from an alveolar duct into an alveolar sac
* means "entrance chamber"
69
type I cells
* A single layer of squamous epithelia
* make up the wall of each alveolus
* surrounded by a delicate basal lamina
* 15 times thinner than a sheet of tissue paper
* Allow rapid diffusion of respiratory gasses
70
respiratory membrane
* AKA the Air-Blood barrier
* the combination of alveolar and capillary walls and their fused basal laminae
* where oxygen and CO2 are exchanged between the alveolus and blood
* Type I cells
71
Type II Cells
* Cuboidal epithelial cells
* scattered among Type I squamous cells
* secrete a fluid that coats the internal alveolar surfaces
72
Surfactant
* a detergent-like substance found in the fluid secreted by type II cuboidal cells
* reduces the surface tension within alveoli
* w/o it the inner walls of an alveolus would stick together during exhalation
73
Features of lung alveoli
* surrounded by fine elastic fibers
* adjacent alveoli interconnect via *alveolar pores*
* Internal alveolar surfaces provide a site for free movement of *alveolar microphagesˆ*
74
Alveolar Pores
* allow the equalization of air pressure throughout the lung
* provide alternative routes for air to reach alveoli whoe bronchi have collapsed because of disease
75
Alveolar Microphages
* dust cells
* live in the air space and remove the tiniest inhaled particles not trapped by mucus
* migrate from alveoli superiorly into the bronchioles
* ciliary action carries them into the pharynx to be swallowed
* 2 million dust cells are cleared each hour
76
Pleura
* a flattened sac around each lung
* serous membrane
* parietal pleura
* visceral pleura
* pleural cavity
77
Parietal Pleura
* covers:
* internal surface of the thoracic wall
* superior surface of diaphragm
* lateral surfaces of mediastinum
* continuous with visceral pleura
78
Visceral Pleura
* Covers the external lung surface
79
Pleural Cavity
* The space between the parietal and visceral pleurae
* surgeons must be aware of the inferior margin of the cavities because cutting into it could cause the lung to collapse
80
Lungs
* Occupy all the thoracic cavity lateral to the mediastinum
* cone shaped
* anterior, lateral, and posterior surfaces contact the ribs
81
Apex of Lung
* deep to the clavicle
* rounded, superior tip of lung
82
Base of lung
* concave inferior surface that rests on the diaphragm
83
Hilum of lung
* on the medial side of lung (mediastinal)
* an indentation through which blood vessels, bronchi, lymphatic vessels, and nerves enter and exit the lung
84
Root of the lung
* the structures that attach the lung to the mediastinum
* largest components:
* pulmonary artery
* pulmonary veins
* primary bronchus
85
Cardiac Notch
* a deviation in the anterior border of the left (smaller) lung that accomodates the heart
86
Lobes of the lungs
Left Lung:
* Superior lobe
* Inferior lobe
* divided by the oblique fissure
Right Lung:
* superior lobe
* middle lobe
* inferior lobe
* divided by the oblique and horizontal fissures
87
broncho pulmonary segments
* segments in each pulmonary lobe
* separated by thin partitions of dense connective tissue
* receive air from individual segmental bronchus
* approximately 10 segments in each lung. Similar but not identical
88
Lobule
* The smallest subdivision of the lung that can be seen with the naked eye
* appear as small hexagons
* each lobule is served by a large bronchiole and its branches
89
pulmonary arteries
* deliver oxygen poor blood to lungs for oxygenation
90
pulmonary capillary networks
* the smallest arteries feed into this around the alveoli
91
pulmonary veins
* carry oxgenated blood from alveoli of lungs to the heart
92
Pulmonary ventilation
or
breathing
* consists of two phases:
* inspiration (inhalation)
* expiration (exhalation)
93
Inspiration
* Lungs increase volume and decrease pressure
* decrease in pressure causes air to flow into it
94
Action of the diaphragm
* Dome shape diaphragm contracts, moves inferiorly, and flattens (superoinferior expansion)
* vertical dimension (height) of thoracic cavity increases
* lower ribs elevate, aiding in lateral expansion of thorax
* *Phrenic Nerve:*
* *paired nerve that innervates the diaphragm on each side to control rate of breathing*
95
Pneumothorax
* when air enters the pleural cavity and the lung collapses (Pneumothorax)
* air breaks the seal of pleural fluid that holds lung to the thoracic wall and lung collapses like a deflating balloon
* usually results from:
* chest trauma
* overexertion that raises intrathoracic pressure and causes lung to pop
* a wound that penetrates thoracic wall
* disease process that erodes a hole through the external surface of the lung
* obstruction of a bronchus by mucus, tumor, inhaled object or enlarged lymph nodes
* Reversed surgically by closing the hole that penetrated pleural cavity and withdrawing air from the cavity using chest tubes
96
expiration
* Inspiratory muscles relax
* rib cage drops under gravity
* relaxing diaphragm moves superiorly
* elastic fibers within lungs recoil
* volume of thorax and lungs decrease simultaneously
* pressure within lungs increases and pushes air out
97
Forced expiration
* Contraction of muscles in the abdominal wall
* oblique and tranversus abdominus
* Contractions
1. increase the intra-abdominal pressure, forcing the diaphragm superiorly
2. sharply depress the rib cage, decreasing thoracic volume
* intercostal muscles and latissimus dorsi also help depress rib cage
98
Respiratory distress syndrome
RDS
* pulmonary surfactant is not produced until the end of fetal life
* in infants, alveoli can collaps during exhalation and must be completely reinflated during each inpiration
* requires tremendous energy that can lead to exhaustion and respiratory failure
* responsible for 1/3 of all infant deaths
* treated by
* using positive pressure respirators to force air into alveoli and keep them inflated between breaths
* natural or articficial surfactants
99
Bronchial Asthma
* a respiratory condition
* affects 7% of adults and 10% of children and on the rise
* allergic inflammation in people who are hypersensitive to irritants in the air or stress
* attacks can be triggered by
* inhaling substances to which the sufferer is allergic
* inhaling dust or smoke
* respiratory infections
* emotional upset
* breathing cold air
* Symptoms:
* coughing
* wheezing
* shortness of breath
100
Cystic Fibrosis
CF
* an inherited disease in which the functions of exocrine glands are disrupted throughout the body
* occurs mainly in people of European descent
* kills 1 of every 2400 americans
* Causes an oversecretion of viscous mucus by the bronchial glands
* mucus clogs respiratory pathways and acts for a feeding ground for bacteria
* death comes from infection
* Modern antibiotics allow the avg patient to live until age 30
* excess chloride in epithelial cells cause the body's antibiotics to become ineffective
101
Chronic Obstructive Pulmonary Disease
COPD
* A category of disorders in which the flow of air into and out of the lungs is difficult or obstructed
* Refers mostly to
* Chronic bronchitis
* obstructive emphysema
* Features:
* patients almost always have a history of smoking
* experience a labored breathing called *dyspnea*
* coughing and pulmonary infections occur frequently
* Most victims develop respiratory failure
102
Dyspnea
* bad breathing
* a labored breathing developed in COPD patients
103
Chronic Bronchitis
* a COPD
* inhaled irritants lead to
* a prolonged secretion of excess mucus by the mucosa of the lower respiratory passages
* inflammation of mucosa
* fibrosis (formation of scar tissue) of mucosa
* Airways are obstructed
* ventilation and gas exchange are impaired
* Stagnant pools of mucus become infected, viruses form
104
Obstructive Emphysema
* a COPD
* permanent enlargement of the alveoli
* caused by deterioration of alveolar walls
* caused often by smoking
105
Epistaxis
* nasal hemorrhage or nose bleed
* follows
* trauma to the nose
* nose picking
* excessive nose blowing
106
Epiglottitis
* rapid inflammation and swelling of the epiglottis
* usually ages 2-7
* associated with fever, sore throat, and difficulty swallowing
* upper airway infection by bacterium *haemophilus influenzae*
* can obstruct breathing
* in elderly it also involved pharyngeal structures
* treatments include
* keeping airway clear
* antibiotics
* vaccination against bacterium
107
Olfactory Placode
Week 4: a thickened plate of ectoderm that appears on each side of the future face
Placodes invaginate to form olfactory pits that form nasal cavity, connect with pharynx
108
laryngotracheal bud
* a tubular out pocketing off the pharyngeal foregut
* give rise to lower respiratory organs
* proximal part forms trachea
* distal parts form bronchi
109
Aortic Bodies
Carotid Bodies
* Aortic bodies send their sensory info to the medulla through the vagus nerve
* Carotid bodies send their info through the glossopharyngeal nerves
* more important chemoreceptors for regulating respiration
110
Upper respiratory Tract
111
pneumothroax
43. Pneumothorax is a collapsed lung as a result of air entering the pleural cavity.
112
Respiratory system is fully formed
During young adulthood
