A "mystery molecule" was isolated in a laboratory and scientists found that the molecule readily crossed artificial membranes. Which of the following molecules can be ruled out as the "mystery molecule?"

Question: A "mystery molecule" was isolated in a laboratory and scientists found that the molecule readily crossed artificial membranes. Which of the following molecules can be ruled out as the "mystery molecule?"

a) CO2

b) O2

c) Cl-

d) H2O.

Answer:

c) Cl-

Explanation:

Membranes are the bilayers of phospholipids. The core of the membranes is non-polar and hydrophobic in nature due to the presence of non-polar fatty acid tails of phospholipids. The non-polar core of the membranes does not allow the charged particles such as chloride ions and the other polar and large substances to move through the membrane. The observed molecule could easily cross the artificial membrane. This means that the molecule was not a charged particle such as chloride ions.