Often prevalent in the sciences, undergraduate research experiences (UREs) are highly beneficial engaged learning experiences in higher education. Though the benefits of UREs are well established, there is little information about which students participate in these experiences and the pathways they take to become engaged in them. This study consists of three works which surround the overarching research question: "How do undergraduate science students initialize research experiences such that departments and institutions can improve access to these high-impact practices?" Utilizing the intersection of the theories of Science Capital and Social Cognitive Career Theory, this study provides insight and recommendations into ways in which science departments and their respective institutions can improve the equity of access to UREs. The first section of this sequential explanatory mixed methods study analyzes data from publicly available datasets and a multi-institutional survey. This section analyzed participation rates in undergraduate research across demographic groups and the effect of literature-identified influences on their participation. The second section applies topological data analysis to quantitative survey responses to identify influences common between groups of students that responded with varying numbers of opportunities impacting their undergraduate research participation. Based on the populations that answered the survey, an opportunity presented itself to study an understudied population in the literature of individuals with concealable identities and the intersectionality of the influences on their participation in undergraduate research. The third portion describes the experiences of ten women and the effect of their concealable identities on their interactions with undergraduate research. This study provides a novel approach to considerations of entry into UREs and, by doing so, expands upon the multidimensional data methodologies available in discipline-based education research. The results of this study demonstrate common opportunities and barriers to participation across student communities. Examples of these influences include the benefit of faculty interaction and the importance for positive communication about research experiences and the pathways to entry available to students. Results also provide insight into the ways students' identities influence their experiences and highlight the importance of targeted approaches to meet specific student needs. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]