If you type

what makes peppers hot

into google instead of gw. You would have the answer instantly.

From what I understand, most capsaicin is produced in the placental tissue (the "white meat") but is present in the seeds.

Capsaicin is present in the entire pepper but mostly the membrane and seeds. That is why many cut the seeds and membrane out before using chili peppers in many recipes. Most chilis are plenty hot without them.