In this expanded and thorough lab investigation, AP Biology students (as well as college biology students and introductory high school biology students) will work in lab groups to complete two inquiries. In the first inquiry, students will observe prepared slides of plant and animal cells undergoing various stages of mitosis (the lab includes detailed background, materials list, procedure, data/observations section and thoughtful analysis...teacher will need to provide compound light microscopes and prepared slides of onion cells and animal cells). In the second activity, students will examine the processes of meiosis and crossing over by studying images of Sordaria ascospores. The lab includes a detailed background, materials list, procedure, data/observations and thoughtful analysis section for this activity, as well. The teacher will need to provide photocopied micrographs of Sordario ascospores (easily obtained via a google image search online). This lab satisfies the college board requirements for investigating Mitosis and Meiosis and introduces students to the science of microscopy as well as performing calculations (such as percent error) on their data...all in a fun laboratory setting!