Science Image Library: Gram Stain

Science Image Library
Gram Stain

from Science Prof Online

Gram-stained Staphylococcus @1000xTM

1. Crystal violet, the primary stain in Gram-staining; 2. Rinsing between steps of the Gram stain; 3. Application of iodine mordant during Gram stain; 4 & 5. Application of Gram counterstain, safanin.
Virtual Microbiology

You have free access to a large collection of materials used in a college-level introductory microbiology course!
Prokaryotic Cell, Mariana Ruiz
Gram Stain Procedure (Click on image to enlarge.)
Gram Stained Slides (Click on image to enlarge.)
1 & 2. Gram stained slides, showing + & - bacterial controls on left and right circles of slide and unknown bacteria in center.
Gram-positive Bacteria Under Microscope (Click on image to enlarge.)
1 & 2. Gram stain of StaphylococcusGram-positive @ 1000xTM; 3. Gram stain of Staphylococcus, Gram+ @ 1000xTM+; Gram+ specimen viewed at 100xTM; Gram+ specimen viewed at 400xTM.
Gram-negative Bacteria Under Microscope (Click on image to enlarge.)
1 & 2. Gram stain of E. coli, Gram- @ 1000xTM; 3. Gram stain of Gram-negative bacterial sample @ 1000xTM+.
See More Bacterial Stains Button
Mixed Gram + & Gram- Bacteria Under Microscope (Click on image to enlarge.)
1 & 2. Gram stain mixed sample od Staphylococcus (Gram +, purple cocci) & E. coli, (Gram- pink rods) @ 1000xTM
Didn't find what you need?

Search SPO for a Photo
facebook link
SPO twitter
Tamislinked in page
How to Do a Gram Stain
VIDEO: How to Prepare a Bacterial Smear for Gram Staining
Page last updated 9/2014
Go to Microbiology Image Library MAIN PAGE
The Microbiology Image Library is the largest photo collection on the SPO site. To help you more easily find what you're looking for, select the "See more" link of the sub-topic below that corresponds to your interests or use the search boxes.
The SPO Science Image Library is a continuously growing collection of copyright-free science photographs. If you use one of our free, low-res images, we just ask that you give us credit and provide a link to the SPO website  ( Click on photo to enlarge. To save a photo to your computer, right click on it and select "Save".

For those in need of high-resolution images, we will soon be offering hi-res files of many photos in the Science Image Library. Follow us on Twitter @ScienceProfSPO to get updates on new SPO features and products. If you need a high resolution photo now, please contact us.
Gram Positive Bacteria, Staph. epidermidis @1000xTM
Gram-positive Staphylococcus epidermidis @ 1000xTM+
Gram Negative Bacteria, E. coli @ 1000xTM
Gram-negative Escherichia coli @ 1000xTM
Additional Gram Staining Resources
  • Gram Stain Bite Sized Tutorial: This is an extremely useful tutorial that shows, step-by-step, the Gram-staining procedure and the appearance of Gram+ and Gram- bacterial cells.

Photographic guides to differential stains 
now available!
1. Gram
2. Acid-fast
3. Endopsore

The SPO website is best viewed in Google Chrome or Apple Safari.