This lecture delves into the core signaling mechanisms of nuclear receptors, a diverse group of receptors with a common domain structure. Topics covered include ligand binding, receptor activation, signaling cascades, and regulation. The lecture also explores the impact of endocrine disruptors on the endocrine system, exemplifying how compounds like estrogens and pesticides can affect life. Additionally, it discusses the effects of common compounds like eugenol on the estrogen receptor, highlighting their inhibitory properties. The presentation concludes with further reading recommendations on the nuclear receptor superfamily and the implications of endocrine-disrupting chemicals on chemical communication.