DNA and RNA Staining Lab Purpose: To prepare a histochemical slide of onion root tip during mitosis, in order to observe and identify nucleic acids, through staining. Hypothesis: Make a hypothesis about how staining will aid in identifying the different nucleic acids in plant cells. Safety procedures: Dont get the stain on your skin or clothes.
Lab Procedures: Place slide on a paper towel and put one to two drops of stain on the center Place one onion root tip on the stain and gently mash it with the wood stick. Let stand for 10 minutes Place cover slip on the slide and use the paper towel to push down on the cover slip slightly Observe under low and high power. Record data in table
Copy table onto your lab paper Data Table: StructureStained Color (experimental) DNA RNA Nucleus Nucleolus # observed=__ Cytoplasm Stained Color (expected) Blue/purple Pink/red
Analysis: 1.Draw and label a plant cell from your preparation. Include all visible structures and color it the way it stained. 2.How many nucleoli (on average) did you see in the cells? 3.What are the structural differences between DNA and RNA that may have caused them to stain differently? 4.Explain why certain cellular structures stained the same color (hint: think about what they do or contain)