Getting photos off a SD card onto my mac when theres no portal to put memory stick in

We take photos at work and store the images on an SD memory card in my old mac i used to upload by putting into laptop and saving to a file Ive now tried to do this but discovered that this mac does not have the portal to put the sd memory card in - what can i do now - how do i get these photos off the sd card and onto the mac if i dont have the ability to put the sd card in. Do i need to buy some sort of converter or adaptor? I love mac but everytime they upgrade i feel they leave off the stuff you need. please help? what can i do?

thanks