noun ダウンロード 🔗共有 胸腺 A ductless gland, consisting mainly of lymphatic tissue, located behind the top of the breastbone. It is most active during puberty, after which it shrinks in size. It plays an important role in the development of the immune system and produces lymphocytes. Examples : ""During childhood, the thymus helps the body learn to fight off infections, but it becomes smaller as we get older." " 子供の頃、胸腺は体が感染症と戦うのを助けますが、年を取ると小さくなります。 body organ anatomy physiology medicine biology AIとチャット語彙ゲーム読解練習