Biodiversity Lab: Day 2 Molecular Evidence Ms. Blalock, Ms. Hartsell and Mr. Luckman

Do Now What are some techniques that you can use to determine if two species are similar?

AIM How can we use molecular evidence to determine the relationships between species?

Agenda Do Now INM: Paper Chromatography Test 1: Paper Chromatography Test 2: Indication Test for Enzyme M Test 3: Translating DNA Exit Ticket

Molecular Evidence Yesterday in lab, we used structural evidence to determine the similarities between Botana curus and three other unknown Species X, Y and Z Today in lab, we will be using molecular evidence to determine which of the Species (X, Y or Z) is most similar to Botana curus. Molecular evidence just refers to looking at the similarities and differences of different species based on the molecules (pigments, proteins, DNA) that make up each of the species. We will be performing three different tests to collect this molecular evidence –Paper Chromatography –Indication Test for Enzyme M –Translating DNA into amino acids

Making observations Observations will play a key role in collecting molecular evidence. Specifically, in the Paper Chromatography and Enzyme M tests, observations will be made and recorded about the nature of the reactions that occur.

INM: What is paper chromatography? Paper chromatography is a procedure used to separate substances in a mixture. In this lab, this mixture is a solution of liquid pigments containing different kinds of chlorophyll –It is referred to as “plant extract”

Turn and Talk What is the importance of chlorophyll to a plant?

Separation of pigments The different chlorophyll and other photosynthetic pigments separate out into patterns called “bands” These bands are made up of different colors.

How does it work? Each of the green dots (A, B, C and D) represent plant extract each being from a different species of plant.

What do the results tell you? Plant species that are genetically similar will have similar colors and banding patterns.

Test 1: Paper Chromatography Directions: Using the procedure and PowerPoint titled “ Chromatography”, go through the process of paper chromatography. Purpose: To determine which Species (X, Y or Z) has similar colors and banding patterns as Botana curus. Task: Complete steps 1-7 for the next 15 minutes

Indication Test of enzyme M Botana curus is a plant that produces curol, which is a compound used to treat certain kinds of cancer. There exists no good tests to indicate the presence of curol in plants. However, if a plant produces the enzyme called “enzyme M”, this is a good indication that the plant also produces curol Presence of enzyme M = presence of curol

What happens if enzyme M is present? Just like iodine is an indicator for starch, there exists an indicator for enzyme M. When this indicator comes into contact with a substance that contains enzyme M, the solution will “fizz” or bubble up. This means that if enzyme M is NOT present then there will be no reaction –In other words, nothing will happen

Making connections (3 min) How do you predict the plant extract from Botana curus will react with the enzyme M indicator? Provide reasoning for your response Return to the second page of your guided notes to answer this question.

Test 2: Indication of enzyme M Directions: Following the instructions in your procedure packet, determine which species (X, Y or Z) contains enzyme M Data: Once you have completed the test, record answers in Table 1 under “Indication of enzyme M” column You will have 12 minutes to complete this test.

Test 3: Translating DNA Directions: Following the instructions in your procedure packet, determine which Species (X, Y or Z) contains the most similar amino acid sequence to Botana curus. Data: Record results in Table 1 under “ Translating DNA” Time: You will have 10 minutes to complete this test.

Exit Ticket

Finish Early? Which of the molecular tests ran today do you think is the most accurate at determining relationships between species? Provide reasoning for your response.

Finish early? What was the reasoning behind testing each species for enzyme M? How did you know if enzyme M was present?

Finish Early? How does knowing the amino acid sequence help determine the relationship between species? Explain the relationship between a gene and a protein.