system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is Adaptive Immunity?

I'm struggling to understand the activation of T and B lymphocytes and what they are exactly. And also how antibodies relate to antigens.

Even any resources would be great if they explain university level concepts easily. 

I'm in my first year of my Nursing degree but am really struggling with this whole shebang :(
gpt
So you're in a war against an alien enemy you've never seen before. A scout party (Dendritic Cells) manages to destroy one and yanks off a piece of their armor (Antigen). They report back to their base (Lymph Nodes) to show (present) this piece of armor to everyone and to see if anyone has any answers on how to defeat them. He bounces around all the different weapons inventors (B-Cells) whom all test their weapons against this armor. Most of the B-Cells find that their weapons don't match the armor and will be unable to stick to it. One B-Cell in the Lymph Node finds out that his special rocket launcher (Antibody) is the exact match to defeat this alien armor. The B-Cell then starts making clones of itself (activation and replication) so it can go out and fight the aliens.