Respiratory System Flashcards
What are the major functions of the respiratory system?
- Provide oxygen to body tissues for cellular respiration
- Remove the waste product carbon dioxide
Name the four steps of respiration
- Pulmonary ventilation
- External respiration
- Transport of respiratory gasses
- Internal respiration
list the respiratory structures and organs of the upper respiratory system
nose, nasal cavity, pharynx
list the respiratory structures and organs of the lower respiratory system
larynx, trachea, bronchioles, lungs
What are the conducting zones of the respiratory system?
organs and structures not directly involved in the gas.
Nose, nasal cavity, pharynx, trachea, bronchi, and terminal bronchioles
What is the function of the conducting zones?
provide a route for incoming and outgoing air, remove debris and pathogens from the incoming air, and warm and humidify the incoming air
What is the respiratory zone?
organs where gas exchange occurs
Respiratory bronchioles, alveolar ducts, alveoli, and the microscopic structures within the lungs
What is the function on the respiratory zone?
gas exchange
What is the function of the nasal conchae?
the nasal conchae has many twists and turns causing air to bounce along the epithelium where it is filtered, humidified, and warmed
Why do colds sometimes lead to ear infections?
eustachian tubes connect to each middle ear cavity which open into the nasopharynx
What are the 2 major functions of the larynx?
- helps regulate the volume of air that enters and leaves the lungs
- Allows food to pass and prevents food and beverages from entering the trachea
Name the 3 large cartilages of the larynx
thyroid cartilage (anterior)
Epiglottis (superior)
Cricoid cartilage (inferior)
describe the function of the epiglottis
closes the trachea during swallowing
explain the role of true vocal cords (vocal folds) in sound production
True vocal cords have inner edges that are free which allow them to vibrate when air moves past which results in sound
Describe the relative position of trachea and esophagus
the trachea is inferior to the larynx
The esophagus borders the trachea posteriorly
What is the purpose of the respiratory membrane?
also known as the air blood barrier allows gasses to cross by simple diffusion, allowing oxygen to be picked up by the blood for transport and CO2 to be released into the air of the alveoli
What is the structure of the respiratory membrane?
it is made up of alveolar walls, capillary walls and basement membranes. The alveolar walls consist of type I alveolar cells, type II alveolar cells, and alveolar macrophages
What are type I alveolar cells functions?
highly permeable to gasses
What are type II alveolar cells function?
secrete pulmonary surfactant
What are alveolar macrophages in alveoli function?
remove debris and pathogens
What is the function of surfactant in the lungs?
reduces surface tension of the alveoli
Which muscles are actively involved 8in normal inspiration?
the diaphragm and external intercostal muscles
What is atmospheric pressure?
the amount of force exerted by gasses in the air surrounding any given surface
What is intra-alveolar pressure?
the pressure of air within the alveoli, this pressure changes during the different phases of breathing
What is intrapleural pressure?
The air pressure within the pleural cavity , its less than atmospheric pressure and considered a negative pressure
Why is intrapleural pressure important for pulmonary ventilation?
the difference in pressures between the intrapleural and atmospheric pressure causes pulmonary ventilation because air flows from an area of higher pressure to an area of lower pressure
How is the expansion of the thoracic cavity leads to the air moving into the lungs?
Expansion of the thoracic cavity increases the volume of the thoracic cavity, as the volume increases, the pressure within the cavity decreases creating lower pressure than the atmospheric pressure. This pressure gradient drives air into the lungs
what is respiratory volume?
various volumes of air moved by or associated with the lungs
What is tidal volume TV?
the amount of air that enters and exits the lungs during quiet breathing
define expiratory reserve volume ERV
the amount of air you can forcefully exhale after an average tidal volume expiration
define inspirations reserve volume IRV
the amount of air that can be forcibly inspired after a tidal inspiration
define residual volume RV
the air left in the lungs if you forcibly exhale as much air as possible.
What is Dalton’s law?
the total pressure in the sum of all the partial pressures
what is Henry’s law?
the concentration of gas in a liquid is directly proportional to the solubility and partial pressure of that gas
Explain external respiration
pulmonary arteries carry deoxygenated blood into the lungs from the heart. CO2 is released in the opposite direction of oxygen, from the blood to the alveoli. Occurs as a function of partial pressure differences in oxygen and carbon dioxide between the alveoli and the blood in pulmonary capillaries
explain internal respiration
gas exchange that occurs at the level of body tissue. Occurs as simple diffusion due to a partial pressure gradient
what muscles are used during quiet inspiration?
the diaphragm and external intercostals
what muscles are used during forced expiration?
diaphragm and intercostals, scalene muscles, and obliques
What muscles are used during deep inspiration?
Diaphragm, external intercostal, scalenes and sternocleidomastoid
describe the process of gas exchange in terms of what happens at the level of the alveoli and capillaries
alvioli: oxygen diffuses from alveoli into the blood
Capillaries: carbon dioxide diffuses from the blood into the alveoli to be exhaled
Explain the relationship between oxygen, heme, hemoglobin and red blood cells
hemoglobin is a protein in red blood cells made up of four heme groups
Oxygen binds to the iron in each heme group, allowing one hemoglobin molecule to carry up to four oxygen molecules
describe the relationship between the partial pressure of oxygen and the binding of oxygen to hemoglobin
as the partial pressure of oxygen increases, more oxygen molecules bind to hemoglobin, increasing hemoglobin saturation
what is meant by the affinity of oxygen for heme?
affinity refers to the strength of oxygen binding to hemoglobin
What will happen to the affinity of oxygen on heme if the temperature increases Or pH decreses?
increased temperature or decreased pH lowers the affinity, making oxygen unbind more easily
Describe 3 ways carbon dioxide can be transported in blood
blood plasma: as some carbon dioxide molecules dissolve in the blood
Bicarbonate ion HCO3 which dissolves in plasma
Carried in RBC
Explain the difference between hyperpnea and hyperventilation
hyperpnea- increased depth and rate of ventilation to meet an increase in oxygen demand, seen in exercise and disease
Hyperventilation- an increased ventilation rate independent of the cellular oxygen needs and leads to abnormally low CO2 levels and high blood pH
why does altitude sickness happen?
high altitude has low atmospheric pressure, this makes it more difficult for the body to achieve the same levels of oxygen. Physical exertion in high altitude results in a low amount of oxygen reserves in the blood
