Chapter 16 - respiratory physiology Flashcards
What is ventilation?
mechanical process that moves air into and out of the lungs (breathing)
Oxygen utilization by tissues to make ATP?
Cellular respiration
Ventilation and gas exchange in lungs = ?
External respiration
Oxygen utilization and gas exchange in tissues = ?
Internal respiration
Air sacs in the lungs where gas exchange occurs?
Alveoli
What is the air pathway? (copy paste)
(I’m so sorry)
Air travels down the nasal cavity → Pharynx → Larynx (through the glottis and vocal cords) → Trachea → Right and left primary bronchi → Secondary bronchi → Tertiary bronchi → (more branching) → Terminal bronchioles → Respiratory zone (respiratory bronchioles → Terminal alveolar sacs
What is in the thoracic cavity?
Contains the heart, trachea, esophagus, and thymus within the central mediastinum
What fills the rest of the thoracic cavity?
Lungs
What lines the thoracic cavity wall?
The parietal pleura
What covers the lungs?
The visceral pleura
What is the space between the parietal and visceral pleura called?
The intrapleural space
What did Dr. Seo use to explain the relationship between lung alveoli and pulmonary capillaries for gas exchange?
A fish in a fish tank :)
What are the 3 types of pressure in respiration?
Atmospheric pressure
Intrapulmonary or intra-alveolar pressure
Intrapleural pressure
Which pressure is the pressure of air outside the body?
Atmospheric pressure
Which pressure is the pressure IN the lungs?
Intrapulmonary or intra-alveolar pressure
Which pressure is the pressure within the intrapleural space and contains a thin layer of fluid as a lubricant?
Intrapleural pressure
Intrapulmonary pressure that is lower than atmospheric pressure?
Inspiration (inhalation)
Pressure below that of the atmosphere is called?
Sub atmospheric or negative pressure
Intrapulmonary pressure that is greater than atmospheric pressure?
Expiration (exhalation)
The difference between intrapulmonary and intrapleural pressure is called?
Transpulmonary (transmural) pressure and is positive during inspiration and expiration.
Which of the 3 pressures is the lowest in inspiration AND expiration?
Intrapleural
Pressure difference in Insp/exp for intrapulmonary pressure?
Insp: -1
Exp: +1
Pressure difference in Insp/exp for intrapleural pressure?
Insp: -8
Exp: -5
Pressure difference in Insp/exp for transpulmonary pressure?
Insp: +7
Exp: +6
Which muscle is most important in breathing?
Diaphragm
How does the diaphragm work while breathing?
Contracts in inspiration – lowers, making the thoracic cavity larger
Relaxes in expiration – raises, making the thoracic cavity smaller
Which muscle raises the rib cage during inspiration?
External intercostal muscles
Which muscle lowers the rib cage during forced expiration?
Internal intercostal muscles
which muscle in between the costal cartilages works with the internal intercostals?
Parasternal intercostal muscles
Which 3 muscles are used for forced inspiration; elevates the ribcage more?
The scalenes, pectoralis minor, and sternocleidomastoid
Quiet expiration occurs..?
occurs with the relaxation of the inspiratory muscles (passive process)
Which muscles are used for forced expiration?
Abdominal muscles
What is the breathing mechanism for inspiration? (copy paste)
a. Inspiration: Volume of thoracic cavity (and lungs) increases vertically when diaphragm contracts (flattens) and laterally when parasternal and external intercostals raise the ribs.
Thoracic & lung volume increase → intrapulmonary pressure decreases → air in
What is the breathing mechanism for expiration? (copy paste)
b. Expiration: Volume of thoracic cavity (and lungs) decreases vertically when diaphragm relaxes (dome) and laterally when external and parasternal intercostals relax for quiet expiration or internal intercostals contract in forced expiration to lower the ribs.
Thoracic & lung volume decrease → intrapulmonary pressure increases → air out
Which of the pressures is the highest in inspiration AND expiration?
transpulmonary
What is most oxygen in blood bound to?
Hemoglobin
What changes the affinity of hemoglobin for O2?
PH, temperature, and 2,3-DPG
Affinity decreases at lower pH and increases at higher pH =
Bohr effect
In oxygenated blood:
More unloading occurs at ____ pH.
Lower
How is metabolism and PH related in breathing?
As one raises, the other lowers
How is hemoglobin’s affinity for O2 related to temperature in breathing?
As one raises, the other lowers
______s obtain energy from the anaerobic metabolism of glucose (has no nucleus or mitochondria)
RBC
What is anaerobic metabolism of glucose inhibited by in breathing?
Inhibited by oxyhemoglobin
What are the 3 ways CO2 is carried through blood?
Dissolved in plasma
Carbaminohemoglobin attached to an amino acid in hemoglobin
Bicarbonate ions (majority)
What is the chemical equation for carbonic anhydrase?
H2O + CO2 → H2CO3
What is carbonic anhydrase? (copy paste)
a. Carbon dioxide readily reacts with water in the RBC of the systemic capillaries and plasma
b. Carbonic anhydrase is the enzyme that catalyzes the reaction to form carbonic acid at high PCO2
What is the chemical equation for the formation of bicarbonate and H+?
H2CO3 → H+ + HCO3−
What is bicarbonate and H+? (copy paste)
Carbonic acid is a weak acid that will dissociation into bicarbonate and hydrogen ions. This reaction also uses carbonic anhydrase as the catalyst
When is 2,3-DPG produced?
When a person is anemic or at a high altitude
