Ventilation systems are needed in a <span>multicellular organism to actually obtain oxygen and give out carbon dioxide. Without this ventilation system, it would be very difficult for multicellular organisms to survive. It has been also observed that surface diffusion is not enough for a multicellular organism to breath.</span>
The hydrophobic tails are sandwiched in between because they are ‘water-hating’ leaving the hydrophilic ends (which are ‘water-loving’) to interact with the watery environment inside and outside of the cell. The hydrophobic ends are mainly made of fatty acid chains ( and have no charges) while the hydrophilic ends are made of phosphate molecules that are negatively charged.
