DNA Mutations Virtual Lab: 55 Points

Name:______Date:______Per:______

DNA Mutations Virtual Lab: 55 Points

DUE: ______

Background: Mutations involve a physical change to genetic material that results in the abnormal encoding of protein sequences. The impact of these changes can be insignificant or devastating.

In this lab, you will complete mRNA and protein sequences based on the information provided. You will be given a starting mRNA sequence, its associated amino acids, and a mutation rule. Use these to construct the mutated mRNA sequence. Compare the original and mutated sequences to see the impact of the mutation.

There are several types of mutations:

1. FRAMESHIFT, meaning the reading “frame” changes, changing the amino acid sequence. There are two types:

DELETION (a base is lost)

INSERTION (an extra base is inserted)

1. POINT, a single base is changed, which can cause a change in the amino acid. This is known as:

SUBSTITUTION (one base is substituted for another)

If a substitution changes the amino acid, it’s called a MISSENSE mutation

If a substitution does not change the amino acid, it’s called a SILENT

mutation.

If a substitution changes the amino acid to a “stop,” it’s called a NONSENSE

mutation.

Procedure:

Step 1 – Google “glencoe dna mutations virtual lab” and click the first link.

Step 2 – Click the Mutate Button to see a sequence and a mutation rule. BE SURE YOU ARE GIVEN THE ORIGINAL SEQUENCE. If not, click “mutate” until you have an original sequence.

Step 3 – Read and apply the mutation rule to the original sequence to determine the mutated sequence. Construct the mutated sequence by dragging nucleotides and amino acids to their new locations. Use the information on your codon chart to identify the amino acids associated with the mutated mRNA sequence. Click a nucleotide or amino acid to remove it.

Step 4 – Click “check” to check your answer to be sure it is correct. Fill in Data Table 1.

Step 5 – Click the Mutate Button again to generate another sequence and complete steps 1-3 again. Fill in Data Table 2. Answer the analysis questions.

Data Table 1: 16 pts

Data Table 2: 16pts

Analysis Questions:

1. Which type of mutation (substitution, insertion, or deletion) occurred in Data Table 1 and how do you know? 3pts

______

______

______

______

1. Describe the differences between the original and mutated sequences. 3pts

______

______

______

______

1. How many amino acids were changed? 1pt______
2. What do you think will be the impact of this mutation? Why? 3pts

______

______

______

______

1. Which type of mutation (substitution, insertion, or deletion) occurred in Data Table 2 and how do you know? 3pts

______

______

______

______

1. Describe the differences between the original and mutated sequences. 3pts

______

______

______

______

1. How many amino acids were changed? 1pt______

1. What do you think will be the impact of this mutation? Why? 3pts

______

______

______

______

1. Explain why all mutations are not necessarily harmful. 3pts

______

______

______

______