Science as an enterprise has been and continues to be exclusionary, perpetuating inequities among whose voice is heard as well as what/whose knowledge is recognized as valid. Women, people of color, and persons with disabilities are still vastly outnumbered in science and engineering by their White, male counterparts. These types of imbalances create a gatekeeping culture of inequity and inaccessibility, particularly for traditionally underrepresented students. Science classrooms, especially at the undergraduate level, strive to mimic the broader practices of the scientific community and therefore have tremendous potential to perpetuate the exclusion of certain groups of people. They also have, however, the potential to be a catalyst for equitable participation in science. Utilizing pedagogies of empowerment such as culturally responsive science teaching (CRST) in undergraduate classrooms can mitigate the gatekeeping phenomenon seen in science. Teaching assistants (TAs) engage in more one-on-one time with students than most faculty in undergraduate biology education, yet minimal pedagogical training is offered to them. Therefore, training for improved pedagogical knowledge is important for TAs, but training for CRST is critical as TAs have broad and potentially lasting impact on students. This study explores the ways in which undergraduate biology TAs enact CRST. Using constructivist grounded theory methods, this study examined TAs' reflections, observation field notes, semistructured interviews, and focus groups to develop themes surrounding their enactment of CRST. Findings from this study showed that undergraduate biology TAs enact CRST in ways described by four themes: "Funds of Knowledge Connections," "Differentiating Instruction," "Intentional Scaffolding," and "Reducing Student Anxiety." These findings provide new insights into the ways undergraduate science education might be reimagined to create equitable science learning opportunities for all students.