Antigen is a substance which

$..........$ produces an army of proteins in response to pathogens into our blood to fight with them $:-$

$A$ condition that occurs when the immune system mistakenly attacks and destroys healthy body tissue is called

What can be included in $CMI$?

Secretion of interferon is which type of barrier?

Primary lymphoid organs $- P$
Secondary lymphoid organs $- Q$
$I -$ Appendix, $II -$ Peyer's patches of small intestine,
$III -$ Thymus, $IV -$ Spleen, $V -$ Lymph node, $VI -$ Bone marrow, $VII -$ Tonsils
Select the correct option for $P$ and $Q$.
$\quad P \quad \quad Q$