It basically decreases fluidity and it raises the melting temperature. Now, a cyst double bond like the one shown here. So in systems that are unsaturated and contain a cyst double bond, we see that that bond creates a kink, a bend in that structure, and this interferes with the well defined structure of that membrane. And so this favors membrane fluidity, it decreases the rigidity and lowers the melting temperature of that system. So we see that increasing the length of our fatty acid chains and removing those says double bonds basically makes the membrane more rigid and increases the melting temperature of that membrane. Now, in bacterial cells, bacterial cells tend to basically use these two factors to control and regulate the rigidity or fluidity of the membrane.