词根词缀：a-, an-

【来源及含义】Greek: prefix; no, absence of, without, lack of; not

【相关描述】These prefixes are normally used with elements of Greek origin, a- is used before consonants and an- is used before vowels.

It affects the meanings of hundreds of words.

There are too many words that use these prefix elements to list all of them on this site; however, there are significant examples listed in this and the other units where they exist.

【同源单词】abacterial, abaptism, abarognosis, abasia, abiocoen, abiogenesis

词根词缀：-ase

【来源及含义】Greek: a suffix indicating an enzyme

【相关描述】From Greek diastasis and then (diast)ase, separation, interval [from dia-, through, apart, plus stasis, a standing]; an amylase that converts starch to maltose. Added to the name of a substance it usually indicates an enzyme that hydrolyzes that substance; for example, proteinases hydrolyze proteins and asparaginase hydrolyzes asparagine.

This suffix is also described as the termination denoting an enzyme, suffixed to the name of the substance (substrate) upon which the enzyme acts; e.g., phosphatase, lipase, and proteinase. It may also indicate the reaction catalyzed, e.g., decarboxylase and oxidase. Enzymes named before the convention was established generally have an -in ending; e.g., pepsin, ptyalin, and trypsin.

【同源单词】anhydrase, colipase, creatinase, cyclase, dextrase, glutaminase

词根词缀：hydro-, hydra-, hydr-, hyd-

【来源及含义】Greek: water

【相关词根词缀】 Cross references of word families that refer to "water": aqua-; hydat-; hygro-.

【同源单词】ahydrotaxis, anhydrase, anhydration, anhydride, anhydrobiosis, anhydrous