Structure of RNA (OCR A-level Biology)

This lesson focuses on the structure of RNA and specifically the similarities and differences between this nucleic acid and DNA so that students are prepared for the upcoming lessons on transcription and translation. The engaging and detailed PowerPoint and accompanying resource have been designed to cover part 1 of point 2.1.3 (g) of the OCR A-level Biology A specification which states that students should be able to describe the structure of molecules of messenger RNA, transfer RNA and ribosomal RNA. Students were introduced to nucleotides and the detailed structure of DNA in previous lessons, so this lesson is written to tie in with those and continuously challenge prior knowledge as well as understanding of the current topic.

The lesson begins by reminding students that RNA is a member of the family of nucleic acids and therefore has a number of structural features that are commonly shared with DNA. A quiz round called “A FAMILY AFFAIR” is used to challenge their knowledge of DNA to recognise those features that are also found on RNA such as the chain of linked nucleotides, pentose sugars, nitrogenous bases and phosphodiester bonds. The next task pushes them to consider features that have not been mentioned and therefore are differences as they answer a structured exam-style question on how RNA differs from DNA. Students will learn that RNA is shorter than DNA and this leads into the final part of the lesson where mRNA and tRNA are introduced and again they are challenged to use the new information explain the difference in size. Brief details of transcription and then translation are provided so that students are prepared for the upcoming lessons on protein synthesis.