Question

1. Manometers

a. In lecture we talked about the partial pressure of oxygen in the atmosphere and how this pressure is important for respiration (e.g. recall altitude effects). Why is it not necessary to know or correct for the partial pressures of oxygen in our manometric measurements?

b. Can manometers be used to record any metabolic gas exchange? For example, can they be used to measure carbon dioxide production in yeast during fermentation (the equation for fermentation in yeast is C_6H_12O_6 ---> 6CO_2 + 2C_2H_5OH)? If so, do any steps need to be taken to ensure that pressure changes are attributed to CO_2?

Answer 1

a)

The air that we take in consists of about 21% of the oxygen considering the atmosphere to be measured as 1, and the atmospheric pressure at sea level is about 760mmHg. The partail pressure of oxygen is somewhat about 160mmHg. Hence, the partial pressure of oxygen could be described as the amount of oxygen present in the atmosphere.

The partial pressure of oxygen which is also called as the PaO2, is considered to be the amount of oxygen strength in blood flowing through the arteries. It indicates that at what pace oxygen passes through the lungs towards the blood and is usually modified by uncompromising diseases. The partial pressure of oxygen is quite immense in the alveoli and reduced in the blood of pulmonary capillaries. As a conclusion, oxygen moves through the respiratory membrane from the alveoli into the bloodstream. As compared to this, the partial pressure of carbon dioxide is quite immense in the blood of pulmonary capillaries and reduced in the alveoli.

The amount of oxygen that we take in remains the same at different altitudes. At higher altitudes, when the atmospheric pressure decreases, the partial pressure of the oxygen taken in, also decreases. This further increases the driving pressure of the exchange of gases in the lungs.