Agenda:3/27 Warm-up: Writing Effective Experimental Conclusions DNA Virtual Lab Lab – procedures –Experiment – Record detailed observations –Conclusions: REE, PE, PA Preparation for Tomato DNA Extraction Homework: Lab notebook complete – materials, procedures, observations & conclusions

DNA Extraction DNA Extraction Virtual Lab Title Background information Purpose Materials Procedures Data Conclusion- REE, PE, PA

DNA Extraction Adapted from activities/extraction/

MATERIALS Tomato Dishwashing detergent Ethanol (ethyl alcohol) 50 mL tube Glass stirring rods Meat tenderizer

Start with a tomato Peeled & chunked tomato Grind into a paste using a mortar & pestle Strain the paste using a non-woven cloth to separate the liquid (save) from the residue.

Put the strained tomato into a 50 mL tube Add 1 mL of detergent

Let the mixture sit for 5 minutes

What does the detergent do?

Each cell is surrounded by a cell membrane DNA is in the nucleus of a cell, which is also surrounded by a membrane

The membranes must be broken open in order to get the DNA out of the cell

Detergent: Breaks apart membranes by attaching to the lipids (fats) & proteins in the membranes

The cell and nuclear membranes have been broken apart, as well as all of the organelle membranes, such as those around the mitochondria and chloroplasts. So what is left? Proteins Carbohydrates (sugars) DNA

Pour 20mL of ice cold ethanol (ethyl alcohol) down the side of the tube so that the layers do not mix. Allow to sit undisturbed for 2-3 minutes to allow the DNA mixture to separate out.

Fibrous material = DNA + Spool the DNA with a stirring rod. Transfer into a microfuge tube and add 1 mL of TBE buffer. Label and store on ice.

Add a pinch of meat tenderizer to the mixture

Why? Meat tenderizer is an ENZYME –A protein that helps chemical reactions happen more quickly The enzymes in meat tenderizer break apart proteins

The DNA in the nucleus is surrounded by proteins

The meat tenderizer cuts away the proteins from the DNA

Stir very, very GENTLY!

Tilt your cup & slowly pour a layer of alcohol on top of the pea soup mixture DNA will float up into the alcohol from the pea soup