Question

ordering question
click and drag on elements in order
correctly list the steps of the gram stain in order, starting with the first step at the top.
instructions
iodine, mordant
acetone - alcohol, decolorizer
safranin, counterstain
crystal violet, primary stain

Explanation:

The Gram stain follows a standard sequence:

1. Primary stain: Crystal violet is first applied to stain all bacterial cells purple.
2. Mordant: Iodine is added to form an insoluble complex with crystal violet, locking it in Gram-positive cells.
3. Decolorizer: Acetone-alcohol removes the crystal violet-iodine complex from Gram-negative cells, leaving them colorless, while Gram-positive cells retain the purple stain.
4. Counterstain: Safranin is used to stain the now-colorless Gram-negative cells pink/red, allowing differentiation from Gram-positive purple cells.

Answer:

1. Crystal violet, primary stain
2. Iodine, mordant
3. Acetone-alcohol, decolorizer
4. Safranin, counterstain