"For large animals like beef, a very large fraction of the nitrogen that enters the cow's mouth is excreted out the back end."

VOA: special.2011.04.05

The collagen is excreted by cells themselves, so the matrix is made by cells.

胶原蛋白是细胞自己分泌的,所以说基质也是细胞制造的

耶鲁公开课 - 生物医学工程探索课程节选

The water soluble vitamins tend to be used more immediately by the body not stored and excreted through the urine if consumed in excess, so the body can tolerate more variation in intake of these before you start getting toxicity than is the case with the vitamins on the right.

而水溶性维生素往往都立刻被身体所利用,不会被机体储藏,过剩部分由尿液排出,因此机体耐受过量水溶性维生素的能力,相比起右边这栏里的脂溶性维生素,可是要强得多了

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选