Microbial Diversity Methods Review Test

2.

This biochemical technique has been the traditional method to assess soil microbial diversity, but only a small proportion of microorganisms are determined (1%).

Plating counts
PLFA
CLPP
DGGE
T-RFLP

Correct Answer

A. Plating counts

Explanation

Plating counts is the correct answer because it is a traditional biochemical technique used to assess soil microbial diversity. However, it has limitations as it can only determine a small proportion (1%) of microorganisms present in the soil.

Rate this question:

3.

These are some of the reasons why phospholipids are potentially useful signature molecules to assess microbial diversity:

Important components of membranes of viable microorganisms
Important in respiration process
Phospholipid fatty acids are rapidly metabolized following cell death
They are involved in nutrient mineralization and cycling
They make up a fairly constant proportion of the biomass of organisms

Correct Answer(s)

A. Important components of membranes of viable microorganisms
A. Phospholipid fatty acids are rapidly metabolized following cell death
A. They make up a fairly constant proportion of the biomass of organisms

Explanation

Phospholipids are potentially useful signature molecules to assess microbial diversity because they are important components of membranes in viable microorganisms. They are also rapidly metabolized following cell death, making them a good indicator of recent microbial activity. Additionally, phospholipids make up a fairly constant proportion of the biomass of organisms, allowing for a reliable assessment of microbial diversity.

Rate this question:

4.

This quantitative molecular method is useful when a coarse level of resolution is meaningful. Hint: it is not influenced by PCR biases

CLPP
DNA Microarrays
DGGE
C+G analysis
T-RFLP

Correct Answer

A. C+G analysis

Explanation

C+G analysis is a quantitative molecular method that is useful when a coarse level of resolution is required. It is not influenced by PCR biases, which makes it a reliable technique for analyzing the distribution of C+G nucleotides in a DNA sequence. By determining the C+G content, researchers can gain insights into the stability, function, and evolution of the DNA. This method is particularly valuable when studying organisms with varying C+G content, such as bacteria or different species.

Rate this question:

5.

Molecular methods that are subject to PCR biases

DGGE/TGGE
T-RFLP
RISA
SSCP
DNA Microarrays

Correct Answer(s)

A. DGGE/TGGE
A. T-RFLP
A. RISA
A. SSCP

Explanation

These molecular methods, including DGGE/TGGE, T-RFLP, RISA, and SSCP, are subject to PCR biases. PCR biases refer to the uneven amplification of DNA fragments during the PCR process, leading to inaccurate representation of the original DNA sample. These biases can occur due to variations in primer binding efficiency, template secondary structure, or differences in DNA sequence composition. Therefore, the results obtained from these methods may not accurately reflect the true diversity or abundance of the target DNA molecules in the sample.

Rate this question:

6.

This molecular technique relies on DNA polymorphisms and allows detection of only the labelled terminal restriction fragment.

T-RFLP
RISA
DNA-Microarrays
DGGE/TGGE
G+C analysis

Correct Answer

A. T-RFLP

Explanation

T-RFLP (Terminal Restriction Fragment Length Polymorphism) is a molecular technique that utilizes DNA polymorphisms to detect only the labelled terminal restriction fragment. In this technique, DNA is digested with restriction enzymes, and the resulting fragments are labeled with a fluorescent dye. The fragments are then separated by size using gel electrophoresis and detected using a fluorescence detector. By comparing the fragment sizes with a reference database, T-RFLP can identify and differentiate between different DNA samples based on their unique patterns of restriction fragment lengths.

Rate this question:

7.

This molecular technique consists on the amplification of PCR products of the intergenic spacer.

RISA
C+G analysis
T-RFLP
DGGE/TGGE
SSCP

Correct Answer

A. RISA

Explanation

RISA stands for Ribosomal Intergenic Spacer Analysis, which is a molecular technique used to analyze and compare the diversity of microbial communities. It involves amplifying the PCR products of the intergenic spacer region located between the 16S and 23S rRNA genes. By analyzing the resulting DNA fragments, researchers can identify and compare different microbial species present in a sample. This technique is commonly used in microbial ecology studies to understand the composition and dynamics of microbial communities in various environments.

Rate this question:

8.

This method relies on the ability of single-stranded DNA molecules to fold into unique secondary structures

DNA Microarrays
T-RFLP
DGGE/TGGE
SSCP
RISA

Correct Answer

A. SSCP

Explanation

SSCP (Single-Strand Conformation Polymorphism) is a method that relies on the ability of single-stranded DNA molecules to fold into unique secondary structures. This technique is used to detect genetic variations or mutations in DNA samples. By subjecting the DNA to different temperatures, the single-stranded molecules will adopt different conformations depending on their nucleotide sequence. These conformational changes can be visualized by gel electrophoresis, allowing for the identification of genetic differences. SSCP is commonly used in genetic research and diagnostics to study genetic diseases, identify polymorphisms, and analyze DNA samples.

Rate this question:

9.

This method consists on the separation of DNA clones, which is based on changes in the electrophoretic mobility of DNA fragments as they migrate through a gel containing a linearly increasing gradient of DNA denaturants.

RISA
SSCP
T-RFLP
DGGE/TGGE
DNA Microarrays

Correct Answer

A. DGGE/TGGE

Explanation

This method involves separating DNA clones based on changes in their electrophoretic mobility as they migrate through a gel with a linearly increasing gradient of DNA denaturants. DGGE (Denaturing Gradient Gel Electrophoresis) and TGGE (Temperature Gradient Gel Electrophoresis) are two techniques that utilize this principle. They are commonly used to analyze DNA sequences and detect genetic variations such as point mutations and single nucleotide polymorphisms. These techniques are valuable tools in molecular biology research and have applications in fields such as genetics, genomics, and forensic science.

Rate this question:

10.

This molecular technique allows analyzing thousands of genes. It is not influenced by PCR biases, but it is only accurate in low diversity systems

SSCP
DGGE/TGGE
DNA Microarrays
T-RFLP
C+G analysis

Correct Answer

A. DNA Microarrays

Explanation

DNA microarrays are a molecular technique that allows the analysis of thousands of genes. Unlike PCR biases, it is not influenced by them. However, DNA microarrays are only accurate in low diversity systems. This means that they may not be as effective in analyzing highly diverse genetic samples.

Rate this question:

Microbial Diversity Methods Review Test

All of these are examples of biochemical techniques that are used to assess microbial diversity and community structure in soil:

Quiz Preview

This biochemical technique has been the traditional method to assess soil microbial diversity, but only a small proportion of microorganisms are determined (1%).

These are some of the reasons why phospholipids are potentially useful signature molecules to assess microbial diversity:

This quantitative molecular method is useful when a coarse level of resolution is meaningful. Hint: it is not influenced by PCR biases

Molecular methods that are subject to PCR biases

This molecular technique relies on DNA polymorphisms and allows detection of only the labelled terminal restriction fragment.

This molecular technique consists on the amplification of PCR products of the intergenic spacer.

This method relies on the ability of single-stranded DNA molecules to fold into unique secondary structures

This method consists on the separation of DNA clones, which is based on changes in the electrophoretic mobility of DNA fragments as they migrate through a gel containing a linearly increasing gradient of DNA denaturants.

This molecular technique allows analyzing thousands of genes. It is not influenced by PCR biases, but it is only accurate in low diversity systems