Gram Staining Research Paper

The Gram stain was used to determine if the bacteria was gram positive or negative. A negative test shows a pink color and a positive test is a purple color. When a bacterium is negative it is because it has an outer membrane and a thin layer of peptidoglycan that is much harder to stain. A positive bacterium has a thick layer of peptidoglycan and no outer membrane that can be penetrated by crystal violet.

The next step of the project included preparing a Gram stain to discover the cell shape, arrangement, and if the bacteria is gram positive or

2) Record the shape of the bacteria, the arrangement of the bacteria, and the gram staining characteristics.

Escherichia coli cells would be pink following a gram stain. E. coli is a gram negative cell due to its thin peptidoglycan layer and its outer membrane structure. In the gram staining process, the outer membrane does not play a role in staining but the peptidoglycan

This experiment was given to us to utilized previous knowledge learned throughout the semester to identify a gram negative unknown bacterium. We had to first learn the difference between a gram negative and a gram positive organism. We started off with doing gram stains to determine whether it was positive or negative. Based on the gram stains, a gram positive stains purple and a gram negative stains pink. A gram positive stains purple because the cell walls is made of a thick peptidoglycan layer and doesn’t

Bacteria are prokaryotic, and if you were to observe the two cells under a light microscope, you could distinguish their differences. The biggest distinguishment you can make while carefully observing the two cells, is the lack of a nucleus in a prokaryotic cell as compared to a eukaryotic. Prokaryotes also lack any membrane-bound organelles.

8. Discuss a possible mechanism of Gram Staining in terms of differences in structure and chemistry between the walls of gram-positive and gram-negative

Gram staining is a technique used to determine if the bacteria is Gram positive or Gram- negative. Gram staining procedure uses crystal violet stain, iodine moderator, alcohol decolorizer and safarin counter stain. In Gram- negative bacteria the primary stain will be washed out with the decolorizer and it will be stained with the counterstain. Whereas in Gram-positive bacteria the primary stain will not leave the cell wall. This difference comes from difference in the structure of the cell wall that retains the stain.

From last week’s test, we achieved pure cultural characteristics from the two slants we made. The growth we saw on the agar slant that contained the yellow specimen was a soft, smooth, yellow growth. The growth we saw on the beige specimen was a thin, even, beige growth. Both cultural characteristics were achieved in the appropriate categories. The categories we were looking for contained abundance of growth, pigmentation, optical characteristics, and consistency. Today we will be preparing two bacterial smears from each specimen and Gram staining them. The reason we are conducting this test is to differentiate between two principle groups, gram positive and gram negative and to further know if a pure culture from both organisms was achieved. This is important for classification and differentiation of microorganisms. The Gram stain reaction will help us tell the difference of the chemical composition of bacterial cell walls. The Gram stain procedure uses four different reagents such as crystal violet, gram’s iodine, ethyl alcohol, and safranin. Before the Gram stain is performed we must make two bacterial smears of the two specimens. We placed one loop of distilled water on a clean slide aseptically. He transferred the specimen from the agar slant that contained the yellow growth and placed it on the slide with the water and gently mixed it together in a circular motion approximately the size of a nickel. He let the smear air dry for one minute and gently heat

We began the experiment with conducting a Gram Stain to be able to differentiate if our organism is gram negative or gram positive. The Gram Stain also allows to determine the size of the cell, the cell’s morphology, and arrangement of the cell. Gram negative cells have a LPS outer layer and an inner thin peptidoglycan layer and the gram-positive cells have a

Infection is the invasion and growth of microorganisms such as bacteria, viruses, and parasites that are not normally present within the body. A prokaryotic cell is a simple cell that does not have a nucleus. One of the most common types of prokaryotic cells is a bacterium. Bacteria are differentiated by many factors including shape, chemical composition, nutritional requirements, biochemical activities, and sources of energy (Tortora 76). A patient with an infection in the upper respiratory system will need to have a sputum sample sent to the lab for further evaluation to determine the cause in order to accurately treat the infection. While many microorganisms can be the cause of infection,

Think on this one! Name the gram stain and shape of the bacteria pictured. Name the genus of the organism pictured. Note the size when determining the

The smears were stained with: Crystal Violet, Gram’s Iodine, Decolorizer, and Safranin.1 Smear A was stained a dark purple meaning it was Gram positive and smear B was stained red meaning it was Gram negative. 2 Both the Gram positive and negative slides were observed under the microscope to characterize the shape, size, and arrangement of cells.1 The Gram positive slide had the cell shape of coccus and the cell arrangement was in clusters and tetrads.

The bacteria cell looks like a pill capsule with a long tail called a flagella. Attached to the outside of the capsule like cell are spaghetti like pili. Around the cell is a cell wall. The cell wall, capsule cytoplasmic membrane are all like a wall around the cell. The Ribosomes are like a bunch of tiny little dots within the cell wall. In the middle of the cell is the nucleoid. The cytoplasm is a jell like structure contain of the cells interior parts. The nucleoid is scattered strands of DNA. I looks a lot like pieces of hair woven

In all areas of biology, it is easy to see that structure is related to function. This statement holds true in microbiology as well, the study of microorganisms, including bacteria. One characterizing feature of bacteria is the cell wall, which can generally (although not in all situations) be categorized into one of two categories: either Gram positive or Gram negative. Gram positive bacteria’s cell walls are composed of a large peptidoglycan layer (up to 90% of their cell wall). Within this large peptidoglycan layer, one can find techoic acids, which contribute to the maintenance of cell wall structure, and lipotechoic acids, which attach to membrane lipids. Gram positive bacteria that act as pathogens can also potentially release exotoxins, which can have very dangerous effects on humans. Gram negative bacteria, on the other hand, have a very small layer of peptidoglycan in their cell wall, which is surrounded by an outer membrane. Within the outer membrane, one can find the lipopolysaccharide layer, which is one of the most distinguishing factors of Gram-negative bacteria. It is important to note that Gram negative bacteria fail to possess techoic