生物 せいぶつ がく てき応答 おうとう調節 ちょうせつ物質 ぶっしつでした
seibutsu gakuteki ōtōchōsetsubusshitsudeshita

Noun
Desu Copula

The polite past form of 生物学的応答調節物質

1. Was a biologically active substance.

Past/Perfective
Polite