Yes, anytime you "reply" to a post, it automatically gets stacked on the very top for all to see. If a post gets buried under a ton of other posts and you want it to be seen, your best bet is to "reply" to it to get it "bumped" to the very top post. Replying with "bump" just let's all know that someone doesn't want the post to get buried alive.
Hope this helps! Welcome to the forum!