Search for journal articles on most topics. This multi-disciplinary database is a good place to start if you don't know where else to begin. (EBSCO)
Search an index of journal articles in the life sciences. This database is part of the Web of Science platform and can also be used to track, evaluate, and compare journals and articles. Tools included are the number of citations, the journal's impact factor, and other metrics. (Clarivate)
Search across thousands of comprehensive encyclopedia entries covering all major science disciplines. This database also includes definitions of scientific terms, biographies of well-known scientists, a few textbooks, and Schaum's Outlines. (McGraw-Hill)