Respiratory system Flashcards
The diaphragm is a giant _______.
It stretches across the entire _______ _______.
Giant muscle
thoracic cavity
What happens when the diaphragm contracts? What happens when it relaxes?
Contracts to expand and increase lung volume: this creates negative pressure and air is forced into the lungs (low pressure inside and high pressure outside)
Relaxes to force air out of the lungs
Deoxygenated blood arrives at the alveoli from the ________ artery.
Pulmonary
Oxygenated blood goes from the alveoli to the _________ vein.
Pulmonary
What surrounds the alveoli? What happens in the alveoli?
Capillaries
Gas exchange through diffusion: CO2 and O2
What two structures surround the bronchioles, and what is their function?
Mucous gland and mucosal lining
they make air movement smooth
What is the process of cellular respiration?
C6H12O6 + O2 = CO2 + H2O + energy
Glucose goes into cells and reacts with oxygen from the lungs to produce carbon dioxide and water which goes back to the lungs, as well as energy which is used by the body.
What is partial pressure?
The pressure of an individual gas in a mixture if it occupied the entire volume of the mixture on its own
Pressure gradients: molecules move from _______ to _______ pressure to achieve equilibrium
high to low pressure
Explain the significance of pressure gradients in the lungs.
The PO2 in alveoli is 13.3 kPa, more than the PO2 of the surrounding capillaries, 5.33 kPa. Thus, oxygen diffuses from the alveoli to the capillaries (high to low pressure).
At the same time, the PCO2 in the capillaries is higher than in the alveoli, so CO2 diffuses into the air in the alveoli from the blood in the capillaries.
What is the distribution of oxygen transportation in the blood?
- 5% of oxygen transported by hemoglobin
1. 5% blood plasma
Explain the significance of pressure gradients in gas exchange between capillaries and tissues.
Oxygen-rich blood enters tissues. Capillaries have high PO2 (13.3 kPa) and tissues have low PO2 (5.33 kPa). Oxygen diffuses into the tissues.
Opposite for PCO2. CO2 diffuses from tissues to capillaries. The deoxygenated blood is transported back to the lungs
What are the three methods of CO2 transportation, from least to most prevalent?
Blood plasma
Hemoglobin (in the form of carbaminohemoglobin)
Formation of carbonic acid
What is the process of carbonic acid formation in the body?
What happens after it is formed?
CO2 + H2O = H2CO3
then,
H2CO3 = H+ (cation) + HCO3- (anion)
Carbon dioxide and water in the blood plasma react to form carbonic acid. Then this carbonic acid produces hydrogen and bicarbonate ions. The hydrogen ions combine with hemoglobin which prevents the ions from accumulating in the blood and raising its acidity. This is taken back to the lungs. The bicarbonate buffers (neutralizes acid) in the blood.
What is total lung capacity?
The maximum volume of air that the lung can hold
