10 Respiratory System Flashcards
site of the gas exchange, microscopic structures, respiratory bronchioles - alveolar ducts – alveoli
respiratory zone
function in respiration, olfaction, and speech
Respiratory system
total amount of exchangeable air or the maximum amount of air that can be moved during one respiratory cycle
Vital Capacity
expandability or “stretchiness” of the lungs higher lung compliance makes it easier to expand lungs normally high due to distensibility of lung tissue and surfactant low compliance leads to difficulty in breathing
Lung compliance
gas-liquid boundary, liquid molecules are more attracted to one another than gas resists any force that tends to increase surface area of liquid water- high surface tension; coats alveolar walls →reduces them to smallest size without surfactant to reduce surface tensions, alveoli would collapse
Alveolar surface tension
quite expiration normally passive process - note: forced expiration is active process; uses abdominal (oblique and transverse) and internal intercostal muscles
Expiration
increased volume-decreased pressure - an active process beginning with muscle contraction - changes in thoracic volume and sequence of events during inspiration
Inspiration
supply blood with oxygen for cellular respiration and dispose of carbon dioxide, a waste product of cellular respiration
Respiration
breathing movement of air into and out of the lungs
Pulmonary ventilation
forms a right of cartilage just inferior to thyroid cartilage, pairs of arytenoid, cuneiform and corniculate cartilages
Cricoid cartilage
outermost layer of connective tissue encases C-shaped rings of hyaline cartilage
Adventitial layer of trachea wall
connective tissue with seromucous glands (serum mucus)
Submucosa layer of trachea
ciliated pseudostratified epithelium with goblet cells
Mucosal layer of trachea
connects posterior of cartilage rings -contracts during coughing to expel mucus; coughing increases pressure, constricts the muscle, narrows diameter of trachea
Tracheal muscles
increases diameter for large volumes of air (relaxes trachealis) - skeletal muscle bridges back of “C” cartilage - esophagus is behind trachea; swallow, needs to expand, the esophagus can bulge into backside of trachea because of “c” ring that doesn’t go all the way around
Sympathetic stimulation
windpipe; extends from cartilage of the larynx to branches of primary bronchi - walls supported by C-shaped tracheal cartilages -open part of cartilages face posteriorly towards esophagus - not continuous cartilaginous tube (cartilage in “C” rings around tube) still have ciliated epithelia in tube
Trachea
forms anterior and lateral surfaces of larynx; where adam’s apple is, testosterone makes it bigger
Thyroid cartilage
Polygonal to cuboidal epithelial cells within alveoli that secrete pulmonary surfactant and readily divide following tissue injury to type I alveolar cells.
Type II alveolar cells (type II pneumocytes)
Flattened squamous epithelial cells that line pulmonary alveoli and facilitate gas exchange.
Type I alveolar cells (type I pneumocytes)
oxygen and carbon dioxide in blood circulation
Transport
where simple diffusion of gases takes place Three layers: 1. squamous epithelial cells lining the alveoli 2. endothelial cells of adjacent capillary 3. fused basement membranes between alveolar and endothelial; each tissue has its own basement membrane. Diffusion occurs rapidly because the distance is small and both oxygen and carbon dioxide are lipid soluble
Respiratory membrane
pseudostratified mucosal epithelium composed of columnar epithelial cells with apical cilia often admixed with goblet cells. This epithelium is characteristic of the upper respiratory tract (nasal cavity, sinuses, nasopharynx), eustachian tube, trachea, and large bronchi.
Respiratory epithelium
Tall, pseudostratified sensory epithelium within the caudal portions of the nasal cavity that contains a population of chemoreceptor cells, olfactory receptor cells, that generate the sensation of smell.
Olfactory epithelium
Scroll-like structures within the nasal cavity that are composed of a core of thin bone surrounded by connective tissue and lined by respiratory epithelium; function to help warm and humidify air and trap particulates.
Nasal turbinates
projects over the glottis and covers the glottis during swallowing elastic cartilage; all other structures have hyaline cartilage
Epiglottis
air enters larynx through?
glottis
end of soft palate, prevents air/food from going into the nasal cavity - made of 9 cartilages, ligaments, and skeletal muscles.
uvula
oxygen and carbon dioxide exchange between systemic blood vessels and tissues.
Internal respiration
oxygen and carbon dioxide exchange between lungs and blood.
External respiration
columnar epithelial cells that produce and secrete mucin, a glycoprotein that is a major constituent of mucus.
Goblet cells
pathway moving air; no gas exchange, includes all structures from nasal cavity to larger bronchioles, this also cleanses, warms and humidifies the air and cools the air on way out (maintains homeostasis), facilitates the exchange, needs a head for diffusion, lines with respiratory mucosa with cilia; traps and get rid of particles before they go into lungs; pseudostratified ciliated columnar epithelium
Conducting zone
rich in metabolic enzymes (cytochrome P450 enzymes) and therefore serve a major role in the biotransformation of inhaled xenobiot; cuboidal epithelial cells with apical microvilli located within and distal to bronchioles.
Club cells (Claracells)
like the arterioles of the cardiovascular system; controls the amount of resistance to airflow - extreme bronchoconstriction can almost completely block passage ways no cartilage, all smooth muscle
Bronchioles
trachea branches into two primary bronchi (right/left), one on each lung secondary bronchi branch off primary; enter lung lobes (2 on left lung, 3 on right), one to each lobe tertiary bronchi (9-10 branches each lung) supply bronchopulmonary segment - C shaped rings are now offset, protects from all directions - bronchioles branch into alveoli
Bronchial tree
relationship between the pressure and volume of a gas, gasses fill the container: if the container size is reduced – the pressure increases (P). Pressure varies inversely with volume. Changes in thoracic/lung volume of the pleural cavities – the movement of the chest wall or diaphragm will directly affect the volume of the lung by changing the volume of pleural cavities.
Boyle’s law
chamber that connect to multiple individual alveoli, surrounded by fine elastic fibers and pulmonary capillaries, only to respond to stretching, and recoil; skeletal muscles would be too thick, (we do not want this to prevent gas flow to capillaries)
Alveolar sacs
connect adjacent alveoli and equalizes air pressure throughout the lungs
Alveolar pores
keep alveolar surfaces sterile, 2 million dead macrophages/hour carried by cilia – throat – swallowed.
Alveolar macrophages
composed of a single layer of squamous epithelium (type 1 alveolar cells or pneomocytes), scattered cuboidal type II alveolar cells secrete surfactants and antimicrobial proteins; no gas exchange, secrete oily surfactant in humid/watery environment ( (liquid has the tendency to stick together, try to collapse alveoli) this can be prevented by surfactant. Has an extensive but small capillary network.
Alveoli
Three layers of respiratory membrane
1.squamous epithelial cells lining the alveoli
2. endothelial cells of adjacent capillary
3. fused basement membranes between alveolar and endothelial;
respiratory can be divided into
air conduction portion and respiratory portion
provide oxygen to body tissues for cellular respiration, remove the waste
product carbon dioxide, and help to maintain acid-base balance.
conduction zone
Portions of the respiratory system are also used for non-vital functions such as?
sensing odors, speech production, straining
Air is conditioned by being humidified by?
serous and mucous secretions
air is being conditioned by being warmed? and filtered?
underlying blood vessels,
particles being trapped in mucous
secretions, and transported towards the
throat
In pulmonary ventilation, the air is inhaled
through the
nasal and oral cavities
respiratory process takes place through hundreds of millions of microscopic
sacs called
alveoli
secrete mucus, and are characterized by cytoplasm filled with poorly staining, basophilic material (mucin)
goblet cells
Traditional respiratory epithelium is
ciliated pseudostratified columnar epithelium
paired external apertures of the nasal cavities in our domestic species are
termed
external nares (nostrils)
Consists of the nostrils
and nasal cavity, the pharynx, the larynx, and the turbinates. These structures
allow us to breathe and speak. They warm and clean the air we inhale.
upper respiratory system
Scroll-shaped bones protrude and form spaces through
which the air pass
nasal conchae
swirl the air around to allow the air time to humidify, warm, and be
cleaned before it enters the lungs
nasal conchae
specialized epithelium that facilitates the sense of smell
epithelium mucosa
The olfactory epithelium is tall, pseudostratified epithelium that contains three
distinct cell types
olfactory receptor cells
sustentacular cells
basal cells
modified neurons and chemoreceptor cells
interspersed within the olfactory epithelium
olfactory receptor cells
histologically similar to the respiratory epithelium and have apical microvilli. These cells provide structural and metabolic support to the
epithelium.
sustentacular cells
cuboidal to short polygonal cells that reside adjacent to the
basement membrane
basal membrane
bone-encased, air-filled spaces within the skull that
communicate with the nasal cavities
paranasal sinuses
horse have well-developed and distinct paranasal sinuses that includes
frontal, dorsal conchal, ventral conchal, rostral maxillary, caudal maxillary, and sphenopalatine
have only frontal and maxillary sinuses
dogs
produce mucus and lighten the weight of the skull
paranasal sinuses
conchae, meatuses, and paranasal sinuses are lined by
respiratory epithelium
help remove the mucus and debris from the
nasal cavity with a constant beating motion, sweeping materials towards the
throat to be swallowed
cilia of respiratory epithelium
paired (left and right) specialized chemoreceptor
organs adjacent to the nasal septum within the nasal cavity of domestic species
vomeronasal organs
similar to olfactory receptor cells, are modified
neurons that detect pheromones (e.g. pheromones in urine) and transmit to the
brain via efferent axons
vomeronasal receptors
shaped like a funnel and lined by a mucous membrane that is continuous
with that of the nasal cavities. During respiration, it conducts air between the larynx
and trachea (or “windpipe”) and the nasal and oral cavities
pharynx
Flanked by the
conchae of the nasal cavity, and it serves
only as an airway. The lining epithelium is
pseudostratified ciliated columnar
epithelium
nasopharynx
A passageway for both
air and food. This lies posterior to the oral
cavity and contains the palatine tonsils. The lining epithelium is stratified
squamous epithelium.
oropharynx
Lies anterior to the oropharynx and posterior to the larynx. It continues the route for ingested material and air until its inferior end, where the
digestive and respiratory systems diverge.
laryngopharynx
complex, tubular organ, the structure of which is primarily composed
of elastic and hyaline cartilage and skeletal
larynx
connects the naso- and oro-pharynx with the trachea, functioning in air
conduction, and vocalization, and in obstructing the passage of ingesta into the
trachea during deglutition
larynx
supported by a
series of C-shaped
cartilaginous (hyaline
cartilage) rings
trachea
ends of the
incomplete cartilaginous
rings of the trachea are
connected by a band of smooth muscle called?
trachealis muscle
bronchoconstriction is a life-threatening effect of
massive histamine release, mediated via
mast cell derive histamine
thin-walled airways lined by variably ciliated or non-ciliated columnar epithelium
bronchioles
lack cartilage and glands which, along with their smaller size, distinguish them histologically from bronchi
bronchioles
Bronchioles open into short segments called _______, which are thin- walled branches of the bronchioles
terminal bronchioles
the transition into respiratory bronchioles
terminal bronchioles
rich in cytochrome P450, an enzyme responsible for the biotransformation of inhaled and circulating toxins
club cells
abundant and highly active in hepatocytes, another cell type
responsible for the biotransformation of toxins
P450
production of pulmonary
secretions and progenitor (proliferating)
cells that may repopulate after cell loss
and/or injury
club cells
conducting regions lined by knob-like projections of cuboidal epithelium that cover small amounts of
smooth muscles
alveolar ducts
site of gas exchange in the lungs; elastic, thin-walled structures arranged in clumps
at the ends of respiratory bronchioles
alveolar ducts
Alveoli are thin-walled, sac-like
structures lined by a single layer of
flattened squamous epithelial cells which facilitate gas exchange across their surface
type I pneumocytes
cuboidal epithelial cells frequently residing in the corners of alveolar space responsible for secretion of surfactants
type II pneumocytes
a fluid composed of phospholipids and proteins that coats the
surface of alveolar spaces to reduce surface tension, allowing for alveoli to expand
and remain open
surfactant
Play a crucial role in tissue repair in the lung. Following damage to type I pneumocytes, it proliferate and
differentiate into type I pneumocytes, thereby restoring alveolar
type II pneumocytes
Alveolar spaces contain a resident population of macrophages, always present
on their inner surfaces, where
they ingest and destroy airborne
irritants such as bacteria, chemicals, and
dust.
alveolar macrophages
outer surface of the entire lung parenchyma is covered by? and what type of CT?
visceral pleura, thin loose CT
2 sources of blood supply of lungs
bronchial arterial supply and pulmonary arterial supply
pulmonary arterial circulation originates from
ride side of the heart
s originate from the thoracic aorta and also course along large airways, providing much of the blood supply to these structures, as well as the
pleura.
bronchial arteries
occurs in every body cell when oxygen reacts with glucose to free its energy in chemical
form
cellular respiration
