use yum to install SRPM files?

[Gerald Thompson]

I have an unusual question.

I was thinking of using yum to install the source packages instead of 
downloading the iso files, but I am not sure what to put into the yum 
command to get it to download the newest versions of the SRPMS.

I know how to set the repositories in yum.conf, and I even have a pretty 
fast mirror in my home city that I use.

But what would you type in to install the SRPM files without already 
having them on the system to update, would you have to do one package 
group at a time?

I know I should probably just stop being lazy and just download the ISO 
files and just mount them and install that way, I was just wondering if 
there was a way to let yum download the updated versions and install 
them to the system right directly.

Sincerely,
Gerald Thompson