• Assess student responses during group work for general understanding of translation vs. transcription.
• Collect the Student Questions for individual assessment.
• Incorporate student self-assessment through exit slips/ticket at the end of each lesson.

Preparation:

• Read the Background Biology and Suggestions for Discussion section on pages two through four in the Teacher Preparation Materials–From Gene to Protein (S-B-5-3_Teacher Preparation Document.pdf). This background knowledge will help to guide students in completing the student questions and the modeling activities.
• Create a packet of Modeling Procedure Materials for the students (S-B-5-3_Modeling Procedure Materials-From Gene to Protein.pdf). Each pair of students will need the following materials:

o   DNA molecule (“Beginning of Hemoglobin Gene”) on colored paper (cut the template in horizontal strips)

o   “Second Part of mRNA” strip and 9 RNA nucleotides, cut individually, on a different colored paper. (Each packet should have 1A, 2C, 3G, and 3U.)

o   6 tRNA molecules on the same colored paper as the RNA nucleotides (cut each tRNA rectangle to include three nucleotides under the words “Amino Acid”; one each of the six types of tRNA per packet)

o   6 names of amino acids on a different colored paper (one of each amino acid per packet: leucine, histidine, valine, threonine, proline, and glutamic acid)

Days 1–2

Say, “In this lesson, we are going to put together all that we have learned over the last two lessons. We began this unit by looking at the work of Gregor Mendel and the experiments he did with pea plants. From this we learned some basic principles of inheritance.”

“Can anyone summarize Mendel’s work and how it relates to inheritance?” (Allow students time to respond.)

“From Mendel’s work we went on to take a closer look at DNA replication. What does DNA replication have to do with genetic inheritance?” (Allow students time to respond.)

Hand out copies of the From Gene to Protein Student Handout and the Student Questions (S-B-5-3_From Gene to Protein Student Handout.doc, S-B-5-3_From Gene to Protein Student Questions.doc, and S-B-5-3_From Gene to Protein KEY.doc).

While students are collecting their materials, write the following questions on the board and allow students some time to consult with one other student to come up with the answers.

1.   What is a protein?

2.   The instructions for making a protein are provided by a gene, which is a specific segment of a _____ molecule.

Review the answers and address student questions before moving on.

1.   A protein is a long train of amino acids linked together. Proteins have different functions; they can provide structure (ligaments, fingernails, hair), help in digestion (stomach enzymes), aid in movement (muscles), and play a part in our ability to see (the lens of our eyes is pure crystalline protein).

2.   DNA

Direct students to read pages 1–2 in the student handout and answer questions 1–7 with their partner.

Once they are finished, explain to students that they will use paper models to learn more about transcription and translation. They will model how a cell carries out transcription and translation to make the beginning of the hemoglobin molecule. Explain that hemoglobin is a protein-based component of red blood cells that is primarily responsible for carrying from the lungs to the tissues of the body. Hand out the following to each pair of students:

• Modeling Procedure Materials Packet, as described in the Preparation section of this lesson (see S-B-5-3_Modeling Procedure Materials-From Gene to Protein in the Resources folder)
• tape
• pair of scissors

Review the concept of base pairing covered in Lesson Two.

Explain that a similar base pairing process takes place in transcription but instead of the A–T pairing found in DNA, in transcription, the base adenine pairs with uracil found in RNA.

Instruct students that you will guide them through the transcription process as follows: Students will work with partners to model the actual sequence of steps used by the cell to carry out transcription. Tell students that even though they will be able to think of a faster way to make the mRNA, they should follow the sequence of steps described in their hand-outs in order to learn how the cell actually makes mRNA.

Have each pair of students complete the Transcription Modeling Procedure from their handouts on page 3. Observe pairs to make sure students are following the procedures correctly and using the materials appropriately. Once they have completed the Transcription Modeling Procedures, have students review their answers in the questions document. Reviewing student responses for thoroughness and accuracy can show which students have a strong understanding of the concept and which students may need additional support.

Circulate through the class assisting groups in need of assistance.

Instruct students to summarize what they have learned by explaining how a gene directs the synthesis of an mRNA molecule. They will answer on an exit slip (S-B-5-3_Exit Slip-Days 1 and 2 Template.doc). Instruct students to summarize what they have learned by explaining how a gene directs the synthesis of an mRNA molecule. Tell students to include in their explanation the words and phrases: base-pairing rule, complementary nucleotides, and cytoplasm.

Days 3–4

Begin by allowing students to share responses to the exit slip question given at the end of the last class. Together, students will share best responses and select the most appropriate responses to the question.

Inform students that next they will model the process of translation. Have students review the content previously covered on translation. Begin to clarify concepts on translation. Ask student volunteers to review content and begin class discussion for clarification of concepts. When you have determined that students are ready to move forward, they can begin the Translation Modeling Procedure on pages 5–7 in their handouts.

• Have students return to groups from Day 1.
• Instruct students to read pages 3–4 of the student handout, and then follow the Translation Modeling Procedure.
• Actively monitor student groups as they carry out the procedure, answering questions as needed.

Gather the class together and direct students to work through all of the remaining questions in their questions document.

Once students have answered the questions, they can be given an exit ticket to complete and hand in before leaving (S-B-5-3_Exit Slip-Days 3 and 4 Template.doc).

Instruct students to summarize what they have learned by explaining how a gene directs the synthesis of a protein. Students must include in their explanation the words amino acid, anti-codons, codons, cytoplasm, DNA, mRNA, nucleotide, nucleus, ribosome, RNA polymerase, tRNA, transcription, and translation.

Day 5

Place students in small groups and give each group a poster or chart paper and a marker. Have each group of students brainstorm vocabulary and concepts from Lessons 1 and 2 and jot them down on the poster. They can write words, phrases, sentences, and/or include diagrams or pictures on the poster.

Tell students, “You will be writing a song or rap that is about genetic inheritance. You may use the ideas on your poster and your notes to help you. Your song/rap should clearly explain the roles of DNA, alleles, genes, and chromosomes in inheritance. It should include information about Mendel’s work and also about DNA replication.”

Create and give students a copy of the Genetic Inheritance Song/Rap Rubric and read through it with them (S-B-5-3_Genetic Inheritance Song or Rap Rubric.docx). Answer any questions students have before they begin.

Have students work alone or in groups to write the song or rap. If time permits, have several students present their songs to the class.

Extension:

• For students who need extra practice, show them an example of a genetics song or rap such as those in Related Resources. Allow students to include fewer vocabulary terms in their song or rap.
• For students who may be going beyond the standards, have them include more vocabulary terms in their song or rap.
• Students who may be going beyond the standards can research sickle-cell anemia and write a summary of the causes, symptoms, and treatment of the disorder. Suggested Web sites for research:

www.nhlbi.nih.gov/health/dci/Diseases/Sca/SCA_WhatIs.html

www.hhmi.org/biointeractive/dna/animations.html