Alveolar walls are thin to enable the quick passage of oxygen in and out of the lungs. The lungs works hand-in-hand with the heart and also is responsible in converting blood that's de-oxygenated into an oxygenated blood that is usable by the organ systems of the body. The alveolar walls are also designed to have thin membranes so that it can expand and constrict quickly allowing us to breather properly.
Answer:
The correct answer would be - 9 hours.
Explanation:
The half life of a drug is the time that is required to decrease or reduced to one half of the its original achieved level or the highest amount previously taken. The half life of drug is also known as the time a drug take to complete its action.
At a dose of 500 mg the Fluoxitine drug would be 250 mg in 3 hour as it is given that half life of this drug is 3 hours, 125 mg in 6 hours, and in the end 62.5 mg in 9 hours.
Thus, the correct answer is : 9 hours.
Homologous pairs, Eg. X and Y
One pair in paternal and the other in maternal, obtained during Meiosis.