Tekst:

Match the words below with the phrases in italics which have a similar meaning. There are two extra words. Words: genes; guinea pigs; immune system; mates; offspring; papers 1. We agreed to be volunteers in an experiment because we felt the research was important: guinea pigs 2. By passing on its chemical information in a cell, an animal is able to pass on its characteristics to its offspring: genes 3. The animal's babies survived the winter by hiding underground: offspring 4. We rely on our internal biological structure to protect us against disease: immune system