Beacon Lesson Plan Library

All Aboard for Protein Synthesis

Lisa Davis
Citrus County Schools

Description

Students walk through the process of transcription and translation to demonstrate and understand protein synthesis.

Objectives

The student knows that every cell contains a `blueprint` coded in DNA molecules that specify how proteins are assembled to regulate cells.

Materials

-Large index cards
-String
-Worksheets including Assembling a Protein Molecule Lab, a data table, questions and an answer key (see associated file)

Preparations

1. Prepare the index cards in advance by using the Data Table to determine the cards needed for each protein. Use different color index cards to identify each role. For example: blue (amino acids), yellow (DNA triplets), orange (mRNA codons), and pink (tRNA anticodons).

2. Designate certain areas of the room as the parts of the cell: the nucleus and the ribosome.

3. Make copies of the student handouts in the attached file.

Procedures

The student needs to understand the process of transcription and translation in order to complete the activity. Depending on the level of the learner, you may choose to role play only 1 or 2 proteins or all of them.

1. Pass out copies of the student handouts and go over the information and directions with the students to be sure they understand the task. The handouts in the attached file include the specific information on the activity as well as questions for the students to answer. Steps are summarized below:

A. Students obtain a large index card from the teacher. On this card, they will find their role for the lab. They will have one of four roles: DNA triplet, mRNA codon, tRNA anticodon, or amino acid. They put the cards around their necks.

B. Students report to the area of the cell where they will carry out their roles.

C. The teacher identifies the amino acids that make up the protein to be synthesized. Students use Figure 1 to determine the DNA triplets that code for that protein. They then complete the Data Table for the protein to be synthesized.

D. Students are given the following steps on the handouts:
The DNA nucleotides form a double stranded DNA molecule in which the DNA triplets code for the announced protein.

The DNA molecule unzips to allow the mRNA codons to form. Once the mRNA codons form and leave the nucleus, the DNA molecule reforms.

The mRNA codons move to the ribosomes and line up in the correct sequence.

On the ribosome, tRNA anticodons with the proper amino acids pair up with the correct mRNA codons.

As the mRNA moves along the ribosome, peptide bonds form between the amino acids. When the protein molecule has been made, mRNA, tRNA, and the protein leave the ribosome and return to the cytoplasm.

E. Students repeat steps to form another protein.

2. Circulate, assist, and check for understanding as students complete the activity and the questions on the handouts.

Assessments

Use the data table and worksheet called Assembling A Protein Molecule Lab which is found in the associated file.
The answer key is located in the associated file.
Any students who do not understand may want to walk through the process a few more times or reread the appropriate textbook section or obtain help from the instructor.

Extensions

Web Links

Web supplement for All Aboard for Protein Synthesis
DNA: Genes and Chromosomes

Web supplement for All Aboard for Protein Synthesis
Protein Synthesis

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