Do I need to change my resolution and will InDesign alert me on resolution issues?

Hi

Created an 8.5x11 catalog then realized my images have differeing dpi counts.  300, 240 and as low as 72.  I realize that it will depend on the effective resolution or total size of the original image but is there any alert system in the software to tell me if the image size is going to be a problem when printing?  What are the parameters it uses to make that alert?

Thank you