Look Inside of a Cell from Genetic Science Learning Center
DNA Structure and Replication from Hank and John Green's CrashCourse
Look at Virtual Cell Animations from Molecular and Cellular Biology Learning Center
What Do Cells Do? from Science Education for Public Understanding Program
Check out Interactive Science: Human Anatomy for 3D interactive models by going to LIRN, logging in, clicking the subject titled 'Health & Medical,' and clicking 'Gale Interactive: Human Anatomy.