The minerals are present in small amounts in food and as a function of body weight as well.

矿物质,在食物中所占比例非常小,在体重中所占比例也非常小

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

So can be changed slightly, depending on tense, past, present or future as well as whether or not you want to ask a question.

因此这个句型要根据不同的时态，如过去时、现在时和将来时，作出一点调整；另外也会根据是否是问句而略有不同。

There is 课堂 - SpeakingMax英语口语达人

It's not as simple as DNA going to RNA going to protein, because proteins need to be present in order to make these things happen as well.

基因表达不是简单的从DNA到RNA,再到蛋白质,因为整个过程需要,不同酶的催化作用

耶鲁公开课 - 生物医学工程探索课程节选