Part 1 Flashcards
What is the value of the atmospheric pressure?
760 mmHg
Partial pressures determines the movement of oxygen and carbon dioxide in the atmosphere, the lungs, the blood and the cells. TRUE OR FALSE?
TRUE
Gas exchange does not increase the CO2 content and it does not also decrease O2 content in alveoli air. TRUE OR FALSE?
FALSE
When air is inhaled it becomes humidified due to the moist mucosal lining, this causes water content to increase and the relative percentage of oxygen decreases. TRUE OR FALSE?
TRUE
During exhalation oxygen content is greater in air than carbon dioxide content in the alveoli air, this is because it mixes with air in the airways. TRUE OR FALSE?
TRUE
Exhaled air is not a mixture of alveolar air and air in the anatomical dead space. TRUE OR FALSE?
FALSE
“The quantity of gas dissolving in liquid is proportional to its partial pressure and solubility.” Is this Henry’s law or Dalton’s law?
Henry’s law
The higher the partial pressure of a gas over a liquid and the higher the solubility, the more the gas will stay in solution. TRUE OR FALSE?
TRUE
How much Nitrogen is inhaled?
78.6%
Little Nitrogen is dissolved at sea level due to low solubility. TRUE OR FALSE?
TRUE
Describe the events External respiration
- Pulmonary gas exchange
- Diffuse of O2 to blood capillaries and CO2 in the opposite direction
- Each gas is moving to an area of low partial pressure
- Converts deoxygenated blood to oxygenated blood
What events take place during Internal respiration?
O2 and CO2 exchange between systemic capillaries and tissue cells, also known as systemic gas exchange.
How much oxygen is used by the body during resting period?
25%, the rest is retained in deoxygenated blood.
In the systemic circulation the partial pressure of O2 decreases significantly due to gaseous exchange of oxygen from the blood into the cells and partial pressure of CO2 increases slightly. TRUE OR FALSE?
TRUE
Atmospheric partial pressure of oxygen is greater than carbon dioxide. TRUE OR FALSE?
TRUE
The partial pressures of O2 and CO2 remains the same in deoxygenated blood from systemic circulation. TRUE OR FALSE?
TRUE
What are the four factors that can affect diffusion?
- Partial pressure differences - the greater the difference the faster the diffusion
- Surface area of gas exchange - The larger the surface area the greater the gas exchange (diseases such as emphysema will reduce this)
- Distance of diffusion - Thin membranes will have a rapid diffusion rate that thick membranes (diseases such as pulmonary edema will increase thickness of diffusion pathway)
- molecular weight and solubility - CO2 has a greater solubility to blood than O2 (In disease O2 is usually the most insufficient)
What are the roles of erythrocytes when it comes to transport of oxygen and carbon dioxide?
Provides heamoglobin
Carbonic anhydrase
CL-HCO3 exchanger, CL shift
The transport of gases does not occur by erythrocytes binding and it also does not occur by bulk flow. TRUE OR FALSE?
FALSE
What does Fick’s law describe?
It describes diffusion rates
The largest percent of CO2 is carried as HCO3 ions. TRUE OR FALSE?
TRUE
Partial pressure of oxygen is not the most important factor for oxygen binding and separating. TRUE OR FALSE?
FALSE
What happens to oxygen dissociation curve at high and low acidity (pH)?
High pH - it shifts to left
Low pH - it shifts to right
What happens to oxygen dissociation curve at high and low Temperature?
High temperature - shifts to right
Low temperature - shifts to the left
What happens to oxygen dissociation curve at high and low Pco2?
High Pco2 - it shifts to the right
Low Pco2 - it shifts to the left
Fetal hemoglobin has a different structure than adult hemoglobin, it binds to oxygen with greater affinity and has binds BPG with lower affinity. TRUE OR FALSE?
TRUE
Fetal hemoglobin does not carry 30% more oxygen than maternal hemoglobin. TRUE OR FALSE?
FALSE
Terminal AAs of alpha and beta chains bind CO2 as carbaminohemoglobin. TRUE OR FALSE?
TRUE
70% of carbon dioxide diffuses into the red blood cells and is converted to carbonic acid by carbonic anhydrase. TRUE OR FALSE?
TRUE
Bicarbonates are not exchanged for chloride ions in the plasma (this is known as the chloride shift ). TRUE OR FALSE?
FALSE
What is the Haldane effect?
The lower the amount of oxyhemoglobin, the higher the co2 transport capacity in the blood.
What is reverse chloride shift shift in blood plasma?
It is when bicarbonate ions are exchanged for one chloride ion from RBC into the plasma.
When does chloride shift occur?
It occurs when blood gives up oxygen and receives carbon dioxide.
Reverse chloride shift occurs in the lungs. TRUE OR FALSE?
TRUE
The chloride is used to balance charge. TRUE OR FALSE?
TRUE
The medulla oblongata is part of the central chemoreceptors and detects protons in the cerebrospinal fluid. TRUE OR FALSE?
TRUE
The peripheral chemoreceptors contains aotic bodies and carotid bodies. TRUE OR FALSE?
TRUE
When does the peripheral chemoreceptor start firing?
When there is a decrease in the partial pressure of oxygen, there will be an increase in the non carbon acid via H+
When does the central chemoreceptor start firing?
When there is an increase in partial pressure of carbon dioxide.
What does the central and peripheral do?
They stimulate the medullary inspiratory neurones and they increase firing of the motor neurones to diaphragm and external intercostal muscles which increases ventilation
