What was the main function of the protocell’s fatty acid membrane?
a. to allow sulfur dioxide to enter into the cell.
b. to allow the cells to communicate with each other.
c. to allow chemical compounds to enter into the cell.

The correct answer is option c.

Explanation:

Protocells refer to the first cell-like compositions, which are generated by self-arrangement of macromolecules in the membrane-bound spheres known as microspheres that possess the tendency to differentiate and proliferate. The protocells comprise the RNA ribozyme and the fatty acid double membrane.  

The prime activity of protocell's fatty acid membrane was to permit the chemical compounds to get within the cell by membrane absorption so that the cells can grow and reproduce with the assistance of these organic components. Afterward these reproducible cells may get selected by natural selection, and they may develop to give rise to prokaryotic cells.  

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation: