Quick Answer: What Is Meant By The Term Gram Variable?

The term “gram variable” refers to organisms that take up the positive (crystal violet) stain variably. Frequently, organisms such as Clostrid- ium species will be gram-variable or even appear frankly gram-negative on smears made directly from patient spec- imens [I1d].

What is the meant by gram variable?

Gram-variable organisms are those that cannot be grouped as either negative or positive. The appearance of organisms that stain gram-positive or -negative means that the smear contains organisms. These organisms may be pathogenic or nonpathogenic.

Why are cells gram variable?

Gram staining differentiates bacteria by the chemical and physical properties of their cell walls. Gram-positive cells have a thick layer of peptidoglycan in the cell wall that retains the primary stain, crystal violet. This gives rise to gram-variable and gram-indeterminate groups.

What bacteria are gram variable?

Gram-negative cocci include Neisseria gonorrhoeae, Neisseria meningitides, and Moraxella species. Gram-negative bacilli include Escherichia coli, Pseudomonas species, Proteus species, and Klebsiella species. Gram-variable organisms include Actinomyces species.

What does the term variables mean?

A variable is a quantity that may change within the context of a mathematical problem or experiment. Typically, we use a single letter to represent a variable. The letters x, y, and z are common generic symbols used for variables.

What is meant by Gram variable quizlet?

What is meant by Gram variable? Some organisms are Gram-variable (that means, they may stain either negative or positive) Why are some bacteria Gram positive and others Gram negative? Bacteria is either Gram-positive and Gram-negative based on the chemical and physical properties of their cell walls.

What is meant by Gram indeterminate organisms?

Definition. noun, singular: gram-indeterminate bacterium. Bacteria that do not respond to gram staining and, therefore, are indeterminate as either Gram-positive or Gram-negative.

Why does gram variable reaction occur?

Variations in Gram Reaction Cell wall damage of bacteria due to antibiotic therapy or excessive heat fixation of the smear. Over- decolorization of the smear. Use of an Iodine solution which is too old, i.e. yellow instead of brown in color (always store in a brown glass or other light opaque containers).

What are gram variable bacteria give an example of a gram variable bacteria?

Gram-variable: bacteria that partially retain the purple color of the crystal violet in the Gram stain; most com- monly seen with Bacillus spp., Clostridium spp., Acineto- bacter spp., Streptococcus pneumoniae.

Is Bacillus a gram variable?

If gram-positive (or gram-variable) bacilli contain spores, Clostridium or Bacillus species are likely [T1] [I1d]. Although the Gram stain is used for detection and differentiation of bacteria, other microorganisms, most frequently yeasts and fungi, can be seen on a Gram-stained smear.

What is difference between gram positive and Gram negative bacteria?

Difference in structure of Gram positive vs Gram negative bacteria. Gram positive bacteria have a thick peptidoglycan layer and no outer lipid membrane whilst Gram negative bacteria have a thin peptidoglycan layer and have an outer lipid membrane.

What is the meaning of Gram positive bacteria?

Gram-positive bacteria are bacteria with thick cell walls. In a Gram stain test, these organisms yield a positive result. The test, which involves a chemical dye, stains the bacterium’s cell wall purple. Gram-negative bacteria, on the other hand, don’t hold the dye.

What is gram positive and Gram negative bacteria?

Bacteria with thick peptidoglycan are called gram positive. If the peptidoglycan layer is thin, it’s classified as gram negative.

What is variable definition and example?

The definition of a variable is something that can change, or is a quantity in an equation that can change its value. In the equation 2x+3 > 0, x is an example of a variable.

What is variable answer?

Answer: A variable is a datatype whose value can not be fixed. It can be change based on other parameters. For example, Let X is a variable so that its value can be anything like 1,2,3 or a,p,r, or any word. It can not be fixed.

What does term mean in math?

A term is a single mathematical expression. It may be a single number (positive or negative), a single variable ( a letter ), several variables multiplied but never added or subtracted. Some terms contain variables with a number in front of them. The number in front of a term is called a coefficient.