The Major function of the respiratory system is to exchange oxygen and carbon dioxide. Inhaled oxygen enters the lungs and reaches the alveoli, the layers of the cells lining the alveoli and the surrounding capillaries are each only one cell thick and are in very close contact with each other, the barrier between air and blood averages about 1 micron in thickness. Oxygen diffuses quickly through the air-blood barrier into the blood in the capillaries. Similarly, carbon dioxide passes from the blood into the alveoli and is then exhaled.
Answer:
The cells are connected by gap junctions.
Explanation:
A gathering of protein channels, which permits small molecules and ions to move between the neighboring cells is termed as a gap junction. The protein channels that form gap junctions comprise two connexons, of which one is situated in the membrane of one cell that combines and aligns with the connexon of the adjacent cell.
This association produces a spontaneous pathway, which permits the small molecules and ions to pass passively from one cell to another. The gap junctions are found in all the kinds of cells, however, they are not found in skeletal muscle, RBCs, and blood lymphocytes.
Thus, the passing of the fluorescent dye from one cell to another shows that the two cells are connected with the help of gap junctions.
<em> I </em>believe that it would be B .
