Shows signifant total count but no visual peaks

[Tuur Wynendaele]

For my master’s thesis I’m comparing transcriptomes between two populations. At first sight there seem to be no peaks in the green group where there are peaks in the blue group, but when I hover over the base pairs I notice a significant number of total counts. This applies only for the exonic regions.  Instinctively, I would expect to see some peaks in the green group as well, considering the data ranges on the left. (see screenshots below)

I also have a question regarding the information in the brackets after the A/C/G/T.  I can’t find the meaning behind the ‘+’ and ‘–’  online.

Thank you 

[igv-help]

I can't help you with green and blue group questions,  but + and - refer to the read alignment strand.