Lesson Plan #: AELP-GET0201
An Educator's Reference Desk Lesson Plan
Submitted by: Maryann Lannan
School/University/Affiliation: Massapequa H.S., Ames Campus, Massapequa, NY
Date: May 30, 2001
Grade Level: 9, 10
Duration: 40 minutes
Description: Students learn about the process of protein synthesis through the use of a fairy tale analogy. Prior to this lesson, students should already have knowledge about DNA structure, RNA structure, and complementary base pairs.
Goal: For students to understand the biochemical process of protein synthesis.
- Students will be able to describe the process of protein synthesis.
- Given a "code," students will be able to ascertain the amino acid sequence.
- Replication - Synthesis of an identical copy of a DNA strand.
- Transcription - Synthesis of mRNA molecule.
- Translation - Synthesis of polypeptide from amino acids.
- Codon - Base triplet on mRNA.
- Anticodon - Complementary triplet on tRNA.
- Polypeptide - Protein molecule
Review complementary base pairs by having students complete the first part of the "Breaking the Code" worksheet (DNA replication). Introduce protein synthesis by means of a "fairy tale."
"Once upon a time there were two fraternal twin brothers: Donald N. Armstrong and Ronald N. Armstrong. Donald was the smarter of the two, and he was a successful inventor with many patents. Although Ronald was not as smart as his brother, he was extremely loyal. One day Donald came up with an idea for a solar powered car. Given the ever-present possibility of energy shortage, an efficient solar powered car would be in great demand. However, Donald really didn't want to leave his comfortable estate. He certainly couldn't take a chance by using e-mail or a fax to send his plans to the factory. They might be stolen by industrial spies! Donald knows his loyal brother would do anything for him, so he asks him to be a messenger and carry the plans to the factory. At the factory, the assembly line is set up and factory workers bring the parts to assemble the prototype. The car proves to be enormously successful. The Armstrong brothers buy an even bigger estate and live happily ever after!"
Ask students to relate each part of the story to the corresponding component of the process of protein synthesis:
- Donald: DNA
- Ronald: mRNA
- estate: nucleus
- plans: triplet code
- factory: ribosome
- factory workers: tRNA
- car: protein molecule
Go over complementary bases once more and the differences between DNA and RNA (Ex. RNA substitutes uracil for thymine). Explain the process of transcription and mRNA codons. Have students complete the section of the worksheet about transcription. Explain the process of translation and tRNA anticodons. Then have students complete the section of the worksheet about translation. Lastly, explain how to use the chart on the worksheet to determine polypeptide sequence from RNA codons.
Assessment: After students have completed the worksheet, ask the students to share their answers. Collect students' worksheets to check for completeness.
Useful Internet Resource:
* ThinkQuest: Cellupedia - Protein Synthesis
Special Comments: Play up the fairy tale -- in my experience the students get a good laugh, and it helps them to remember the process much better.