Cristae are associated with mitochondria.
Cristae are the sub-compartments of the inner membrane of the mitochondria which throws itself into many folds. These structures are known to increase the surface area that is available, in order to promote the productivity of cellular respiration. Cristae are necessary for the normal functioning of mitochondria which are considered as the powerhouse of the cell. The folded cristae contain cylindrical connections to the inner membrane known as the cristae junctions. They also have protrusions which folds and penetrates deep into the inner mitochondrial matrix.