Respiratory System Flashcards
Functions of Respiratory System
Olfaction Filtration, warming and humidification of inspired air produce sound for vocalization responsible for gas exchange helps regulate blood pH
Divisions of Respiratory System
Functional
Structural
Functional Respiratory System
Conducting portion
Respiratory portion
transports air into and out of lungs
Conducting portion
Parts of conducting portion
nose pharynx larynx trachea bronchi bronchioles terminal bronchioles
Parts of respiratory portion
Acinus: respiratory bronchioles alveolar ducts alveolar sac alveoli
Structural Respiratory System
Upper Respiratory Tract
Lower Respiratory Tract
Parts of Upper Respiratory Tract
Nose
Pharynx
Larynx
an external structure that protrudes from the face and supported by nasal bones and cartilage
Nose
stiff hairs within the nostrils at the anterior nares
filter impurities
vibrissae
humidifies the air before conducted into the lower respiratory tract
nasal cavity
a funel tube, about 13 cm long, that starts from the internal nares and extends to the level of cricoid cartilage
pharynx
superior portion that lies posterior to the nasal cavity and extends to the plane of the soft palate
lined with pseudostratified ciliated columnar epithelium where the cilia are sweeping downward
nasopharynx
the intermediate portion of the pharynx that lies posteriorly to the oral cavity and extends from the soft palate inferiorly to the level of hyoid bone
oropharynx
inferior portion of the pharynx that begins at the level of hyoid bone and opens to the esophagus posteriorly and the larynx anteriorly
aka hypopharynx
laryngopharynx
a short passageway that connects the laryngopharynx with the trachea
aka voice box
larynx
consists of 2 fused plates of hyaline cartilage that form the anterior wall of the larynx and give it a triangular shape
thyroid cartilage (Adam’s apple)
the ligament that connects the thyroid cartilage, covered with epithelium that closes the larynx upon swallowing
epiglottis
a ring of hyaline cartilage that forms the inferior wall of the larynx
serves as landmark for making emergency airway (tracheostomy)
attached to the thyroid cartilage by the cricothyroid ligament
attached to 1st cartilage of trachea by cricotrachel ligament
cricoid cartilage
parts of Lower Respiratory Tract
trachea primary bronchi secondary and tertiary bronchi terminal bronchioles acinus
16-20 c-shaped cartilages
a tubular passageway for air that is about 12 cm long and 2.5 cm in diameter
located anterior to the esophagus and extends from the larynx to the superior border of the T5 where it bifurcates into R and L bronchi
most sensitive part that has coughing reflexes
mucosa is lined with pseudostratified ciliated columnar epithelium with goblet cells
trachea
function of trachea
maintain patency of airway
a cartilaginous ridge between the two bronchi and the point where the trachea bifurcates into R and L primary bronchi
Carina
serves as a passageway of air to the right and left lung
primary bronchi
mucosa of primary bronchi
lined with pseudostratified ciliated columnar epithelium with goblet cells
subdivisions of the main bronchi and spread in an inverted tree-like formation
Secondary and tertiary bronchi
lined with simple ciliated columnar epithelium with some goblet cells
larger bronchioles
lined with simple ciliated cuboidal epithelium with no goblet cells
smaller bronchioles
the last airway of the conducting system
terminal bronchioles
composed of respiratory bronchioles, alveolar ducts, alveolar sac and alveoli
acinus or alveoli
branch from the respiratory bronchioles
alveolar ducts
arises from the ducts, contain clusters of alveoli
alveolar sac
basic unit of gas exchange
alveoli
2 types of cells in alveoli
Type I Pneumocyte
Type II Pneumocyte
predominant
simple squamous epithelial cells that form a nearly continuous lining of alveolar wall
Type I Pneumocyte
fewer in number
rounded or cuboidal epithelial cells where free surfaces contain microvilli and secretes alveolar fluid that keep the alveolar walls moist
Type II Pneumocyte
a mixture of phospholipids and lipoproteins that lowers the surface tension of the alveolar fluid thereby reducing the tendency of the alveoli to collapse
surfactant
paired cone-shaped organs that are essential for breathing
are elastic connective tissues, called stroma and are soft and spongy
lungs
parts of lungs
apex
base
hilus
a pointed portion that lies below the clavicles
superior
apex
inferior portion that rests on the diaphragm
base
a slit on the mediastinal surface of each lung where blood vessels of the pulmonary and circulatory systems enter and exit the lungs
hilus
lobes of the lungs
right lung
left lung
consists of 3 lobes (superior, intermediate, inferior) and have 10 bronchopulmonary segements
Right lung
much smaller than right and consists of 2 lobes (superior, inferior) and have 2 bronchopulmonary segments
Left lung
a doubled-layer membrane that covers the lungs and the inside of the thoracic cavities
pleura
outer serous membrane that lines the thoracic wall and mediastinum
contains pain receptors
parietal pleura
inner serous membrane that covers the external surface of the lung
no pain receptors
visceral pleura
Defenses of the Respiratory system
Mucocillary transport
alveolar clearance
reflexes of the airways
escalator system
provides a major defense of the respiratory tract that includes goblet cells, mucus and ciliated epithelial cells
mucocillary transport
macrophage activity is the principal alveolar defense against particles and it includes mucocillary transport, blood flow/vessels and lyphatic vessels
alveolar clearance
includes sneezing, coughing, gagging and bronchospasm/bronchonstriction reflex
reflexes o the airways
Muscles of Breathing
Quiet Breathing
Forced breathing
Quiet breathing muscles
diaphragm muscle
external intercostal muscle
dome-shaped muscle that separates the thoracic from the abdominal cavity
diaphragm muscle
superficial muscle between the ribs that pulls the ribs upward and outward
external intercostal muscle
forced breathing muscles
Inspiration: Sternocleidomastoid Scalene Pectoral Trapezius
Expiration:
Internal Intercostal
Abdominal muscles
sides of the neck
raises sternum
sternocleidomastoid
in the neck
elevates, fix and expand the upper chest
scalene
upper chest
raises the chest to increase the A-P diameter
pectoral
upper back
raises the back upon forced inspiration
trapezius
deep muscles between the ribs
shortens the chest transverse diameter
internal intercostal
pulls down the lower chest
depressing the lower ribs
abdominal muscles
Involuntary Components
Chemoreceptors
Lung Stretch Receptors
Impulses from Other Sources
monitors level of carbon dioxide, oxygen and the pH of blood
Chemoreceptors
Hering-Breuer Reflex
monitor patterns of breathing and prevent overexpansion of lung tissues
Lung Stretch Receptors
e.g. frigtened, angry
autonomic nervous system
Impulses from other sources
integrates breathing with acts such as talking, speaking, singing
voluntary component
process of gas exchange in the body
respiration
exchange of gases between air spaces (alveoli) of the lungs and the blood in the and pulmonary capillaries
External Respiration
exchange of gases between blood and systemic capillaries and tissue cells
Internal Respiration
2 types of respiration
External and Internal respiration
mechanical flow of air into and out of lungs
Pulmonary Ventilation
passage of blood through lung tissue
Pulmonary Perfusion
ratio of ventilation to perfusion that expresses the effectiveness of gas exchange
V/Q ratio
normal V/Q ratio
4L/min air
5L/min blood
atmospheric pressure
760 mmHg
Peripheral Chemoreceptors
Aortic bodies
Carotid bodies