How can you transfer photos from iPhone 4 to Mac OS X version 10.5.8

How can you transfer photos from iPhone 4 to Mac OS X version 10.5.8 using either iCloud or iTunes?

I just got a replacement iPhone 4 (I still have the original as well), and when I look at iCloud on my Mac I don't see an icon for photos listed that I thought would be transferred after backup from my original phone. If I cannot transfer the photos to my new phone, I would at least like them on my computer using iTunes or iCloud, or even another option if there is one. Any help would be great, and 'step by step' help if possible would be appreciated since I find this pretty confusing. Thank you so much!