Ecological Succession – Definition, Types, Mechanism, Examples

Ecological Succession - Definition, Types, Mechanism, Examples

What is Ecological Succession? Ecological Succession Definition Ecological succession is the systematic and predictable process by which species composition in an ecosystem changes over time, progressing from initial colonization to a mature and stable community. Characteristics of Ecological Succession Ecological succession is a fundamental concept in the realm of ecology, delineating the sequential transformation of … Read more

Pyramid of Numbers – Definition, Types, Importance, Examples

Pyramid of Numbers - Definition, Types, Importance, Examples

What is Pyramid of Number? The Pyramid of Numbers is a graphical representation used in ecology to illustrate the distribution of various species in different trophic levels of a food chain. This pyramid provides a quantitative analysis, showing the number of individual organisms present at each trophic level. Unlike other ecological pyramids which might consider … Read more

Triple Sugar Iron (TSI) – Principle, Composition, Procedure, Result

Triple Sugar Iron (TSI) - Test Principle, Procedure, Result

What is Triple Sugar Iron Test (TSIA Test)? Triple Sugar Iron (TSI) agar is a differential solid culture medium. It is mainly used in clinical microbiology to identify and distinguish different Gram negative enteric bacteria such as Enterobacteriaceae family. The medium is prepared in a test tube and it is solidified at an angle. Two … Read more

Kligler’s Iron Agar Test – Principle, Procedure, Result

Kligler’s Iron Agar Test Principle, Procedure, Result

Kligler’s Iron Agar (KIA) is a special solid culture medium which is used in microbiology to grow and differentiate bacteria. It is prepared in a test tube and it is allowed to solidify in slant position, so two region is formed. The upper part is called slant and it is oxygen rich. The lower deep … Read more

Ornithine Decarboxylase Test – Principle, Procedure, Result

Ornithine Decarboxylase Test - Principle, Procedure, Result

What is the ornithine decarboxylase test? Ornithine decarboxylase test is a biochemical test used for identification and differentiation of Gram-negative bacteria mainly Enterobacteriaceae family. It is used for differentiating closely related organisms like Klebsiella and Enterobacter species and also for identifying Proteus. It is the test in which microorganism ability is measured to produce enzyme … Read more

Acetate Utilization Test – Principle, Procedure, Results

Acetate Utilization Test - Principle, Procedure, Results

Acetate utilization test is a biochemical test used to determine the ability of an aerobic organism to use acetate as the sole source of carbon and energy. It is mainly employed in diagnostic microbiology for differentiation of Gram-negative bacteria especially members of Enterobacteriaceae family. This test is commonly used to differentiate Escherichia coli from Shigella … Read more

Methyl Red (MR) Test – Principle, Procedure, Results, Uses

Methyl Red and Voges Proskauer Test

What is Methyl Red (MR) Test? The Methyl Red (MR) test is a biochemical test used in microbiology to identify and differentiate bacteria mainly among Enterobacteriaceae family. It is done to check the glucose fermentation pathway. It is used for detecting mixed-acid fermentation which produces stable acidic end products. In this test the organism is … Read more

Ames Test – Principle, Procedure, Result, Limitation, Applications

Ames Test - Principle, Procedure, Result, Limitation, Applications

What is Ames Test? Ames test is a rapid biological assay which is used to determine whether a chemical compound can cause genetic mutations. It was developed by Bruce Ames in 1970s. It is used as an early screening test for carcinogenic property because chemicals causing DNA mutation are frequently carcinogenic. It is based on … Read more

Voges Proskauer (VP) Test – Principle, Procedure, Results

Voges Proskauer (VP) Test - Principle, Procedure, Results

In 1898, Voges as well as Proskauer (16)characterized the process of fermentation of sugars by a variety of bacteria. They demonstrated that the gas that was produced during the process was a mixture of H2 and CO2 that when they added KOH to the cultures been grown in glucose peptone medium to allow for a prolonged period of incubation in presence of oxygen certain organisms developed a red fluorescent color. While the exact nature of the color was not known in the early days, this technique was suggested to differentiate between the bacterial strains that produced it and ones that didn’t. in 1906 Arthur Harden analyzed the fermentation products of Enterobacter aerogenes. He discovered that when it was surrounded by glucose, the organism made two compounds, acetoin as well as 2,3-butanedio.

Spot Indole Test – Principle, Procedure, Result, Uses

Spot Indole Test - Principle, Procedure, Result, Uses

What is Spot Indole Test? Spot Indole Test is a rapid biochemical test used in diagnostic microbiology to detect the production of enzyme tryptophanase by bacteria. It is a qualitative test that determines whether the organism can degrade the amino acid tryptophan to produce indole. This test is commonly used for the presumptive identification of … Read more

Indole Test – Principle, Procedure, Result, Uses

Indole Test - Principle, Procedure, Result, Uses

What is Indole test? It is a biochemical test used in microbiology to determine the bacteria is producing enzyme tryptophanase. This enzyme help in breaking down amino acid tryptophan. This process occurs when bacteria having tryptophanase utilize tryptophan and the end products is formed. These are indole pyruvic acid and ammonia. In this test bacteria … Read more

Hippurate Hydrolysis Test – Principle, Procedure, Result

Hippurate Hydrolysis Test Principle, Procedure, Result

Hippurate Hydrolysis Test is a biochemical test used for detecting the enzyme hippuricase(hippurate hydrolase) in microorganism. It is used for checking whether the organism can hydrolyze sodium hippurate or not. This process occurs when bacteria having hippuricase is exposed to sodium hippurate. The substrate is hydrolyzed and two end products is formed. The reaction is … Read more