Once docked, the phage delivers its cargo. The tails of some, but not all, phage are contractile, punching a channel through the cell’s envelope to inject the genome, emptying the capsid as you see in this myophage infecting a Bacteroidetes cell. This syringe-like mechanism should be familiar from the related contractile weapons discussed in the last chapter. (You can watch an animation of a contractile myophage tail in action on YouTube.)
