Concept Coach learning activity from USA, interesting idea to give mutichoice questions about correct and mistaken ideas about a concept, in this case membrane structure.
This is a great video which would summarise cell structure and DNA replication in an inspiring way for 2nd year Biology students. Although the last 10 minutes argues against evolution.
These two links are - 'void' other links to pdf files OK
Data based question relating villus structure and intestinal cancer
Data based question: lipase activity/uncertainty in measurements.