In this activity, students explore how a cell uses information from the DNA in its nucleus to produce the proteins that help determine the traits of an organism -- a process called protein synthesis. Students begin by learning what DNA is, what it looks like, and where it is located in the body. Then they learn about the various cell organelles involved in protein synthesis. Next, they explore the process of protein synthesis, first by doing a Web activity, then by writing a description of the process, and finally by comparing their description with their partner's and working together to diagram the process. The activity concludes with a discussion about how mutations can affect protein synthesis and change the structure and function of cells.
- Explore the structure of DNA and its role in the cell and in the human body
- Understand the role of cell organelles in protein synthesis
- Describe the molecular process of protein synthesis
- Understand how mutations can affect protein synthesis and cell structure and function
- One to two class periods
- Journey into DNA Flash Interactive
- Organelles in the Cytoplasm QuickTime Video
- From DNA to Protein QuickTime Video
- DNA Workshop Shockwave Interactive
- A Mutation Story QuickTime Video
1. Ask students:
- What is DNA? Where is it found in the human body?
Then have students do the Journey into DNA Web activity. Ask:
- What is the role of DNA in the cell? In the human body?
2. Show the Organelles in the Cytoplasm video. Ask:
- Which organelles are involved in protein synthesis?
- Why do you think cells that produce large numbers of proteins have more rough endoplasmic reticulum (ER) than cells that produce fewer proteins?
- Identify the kinds of human cells in which you would expect to find the most ribosomes. Explain your answers.
- How is the information about making different kinds of proteins passed on from parents to children?
- What building block molecules make up proteins?
4. Have students write a brief paragraph that describes the steps of the protein synthesis process, from DNA to polypeptide chain. Tell them to incorporate the following terms into their description: DNA, bases, transcription, mRNA, translation, codons, anticodons, ribosomes, polypeptides, amino acids.
5. Have students share their descriptions with a partner and then draw a diagram of the process together.
6. Show the A Mutation Story video. Discuss the following:
- How does a mutation change the DNA structure?
- How does the sickle cell mutation affect the function of red blood cells?
- How can a mutation be harmful in one environment and helpful in another?