Horses and donkeys can mate, but they produce a mule, which is always a sterile animal. this means that they cannot produce viable offspring and are (reproductively)(geographically)tem porally)behaviorally) isolated.

All of the following statements about enzymes are correct except: proteolytic enzymes are also known as proteases. pectin methyl esterase causes browning of cut fruit. cloud loss in orange juice is due to enzyme activity. proteolytic enzymes in fish cause tissue softening during storage.