This study reports about biology undergraduates' writing in a course with genre-based writing instruction. The students read, analyse and synthesise research articles using the Scientific Argumentation Model (SAM), a tool to make explicit the characteristics of the research article genre. We explored to what extent 21 students make a synthesis when writing a review of two research articles and which research article's genre characteristics (rhetorical moves and qualifiers) they use. We defined a synthesis as a task in which students select, organise, and connect the articles' content. The analysis of students' reviews showed that most students made a synthesis of both articles. The articles' objective, supports and main conclusion were mostly reflected in the students' reviews. Most students did not use a qualifier in their final conclusion, and when they did use a qualifier it sometimes did not correspond to their main text, suggesting difficulties with understanding the rhetorical meaning of qualifiers. We suggest, supported by our interview and questionnaire data, that SAM could be useful for understanding, selecting, and organising research articles' content when writing a review. We conclude that the use of SAM could be a first step in synthesising research articles focused on supporting students' rhetorical consciousness.