Tag: microbiology: organisms in industry

Questions Related to microbiology: organisms in industry

What is correct about Escherichia coli and Rhizobium japonicum?

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. E.coli is Gram - and R. japonicum Gram +

  2. Both Gram +

  3. Both Gram -

  4. E.coli Gram + and R. japonicum Gram -

Show answer
Correct Option: C
What is the percentage of mucopolypeptide in the cell wall of Gram (+) bacterium?
botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. $60-70\%$

  2. $70-80\%$

  3. $80-90\%$

  4. $90-100\%$

Show answer
Correct Option: B
Explanation:

The mucopeptide is a peptidoglycan that is insoluble in nature. It is also called as murein. It is present in almost all bacterial cell walls. However, its percentage is higher in cell wall of gram positive bacteria than in cell wall of gram negative bacteria. 

So, B is the correct answer. 

Gram negative bacteria detect and respond to chemicals through the receptors in

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. Muramic acid

  2. Lipopolysaccharide

  3. Porins

  4. Volutin granules

Show answer
Correct Option: B
Explanation:

It holds receptor molecules that help bacteria detect and respond to chemicals in their surroundings

So, the correct answer is 'lipopolysaccharides'

Which is not a characteristic of Gram $(+)$ bacteria?

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. Smooth cell wall

  2. Outer membrane

  3. Prominent mesosomes

  4. Two rings in basal body of flagellum

  5. $70-80\%$ murein in cell wall

Show answer
Correct Option: B
Explanation:

Gram positive bacteria differs from Gram negative bacteria in having multiple layers of peptidoglycan. They have 20–30 nm thick and smooth cell wall. They contain 70-80% murein or peptidoglycan in cell wall. They do not have outer membrane like Gram negative bacteria, which have an outer LPS layer. Due to absence of outer LPS layer, Gram positive bacteria has two rings in basal body of flagellum, one attached to the plasma membrane and one attached to the peptidoglycan wall. They have prominent mesosomes. Mesosomes are folded invaginations of the plasma membrane.

Thus, the correct answer is 'Outer membrane.'

Which one occurs in the cell walls of Gram (+) bacteria only?

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. Peptidoglycan

  2. Lipopolysaccharide

  3. Teichoic acid

  4. None of the above

Show answer
Correct Option: C
Explanation:

Teichoic acids are found within the cell wall of most Gram-positive bacteria such as species in the genera Staphylococcus, Streptococcus, Bacillus, Clostridium, Corynebacterium, and Listeria, and appear to extend to the surface of the peptidoglycan layer.

So, C is the correct option. 

Identify the Gram $(-)$ bacterium

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. Streptomyces coelicolor

  2. Escherichia coli

  3. Ampycolatopsis orientalis

  4. Bacillus subtilis

Show answer
Correct Option: B
Explanation:

Gram-negative bacteria are bacteria that do not retain the crystal violet stain during gram-staining procedure. Gram positive bacteria are bacteria that retain the crystal violet stain during gram staining procedure. Examples of Gram negative bacteria include Escherichia coli, Helicobacter pylori. Examples of Gram positive bacteria include Bacillus subtilis, Streptomyces coelicolor, Streptomyces orientalis (Ampycolatopsis orientalis).

Thus, the correct answer is 'Escherichia coli.'

Glycocalyx is

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. Glycoproteins and glycolipids

  2. Oligosaccharide part of glycolipids and glycoproteins

  3. Lipid and protein parts of glycolipids and glycoproteins

  4. Mucopolysaccharides attached to cell wall.

Show answer
Correct Option: B
Explanation:
  • Glycocalyx or pericellular matrix is a carbohydrate-enriched coating of glycoprotein and a glycolipid that covers the cell membranes of few bacteria, epithelial cells and other cells. 
  • It is mainly used in the recognition of the cell (distinguish between healthy and diseased cells) and also regulates the endothelial vascular tissues.
  • So, the correct answer is 'Oligosaccharide part of glycolipids and glycoproteins'.

Wall is two-layered in

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. Mycoplasma

  2. Archaebacteria

  3. Gram $(+)$ bacteria

  4. Gram $(-)$ bacteria

Show answer
Correct Option: D
Explanation:

On the basis of composition of cell wall, the bacteria are classified into two groups, namely Gram positive and Gram negative bacteria. Cell wall of all bacteria is made up of peptidoglycan. The gram positive bacteria contains thick layer of peptidoglycan. However, Gram negative bacteria contains thin layer of peptidoglycan. Apart from this, it also contains an outer layer of lipopolysaccharide (LPS). Hence, the wall of Gram negative bacteria is two-layered.

Thus, the correct answer is 'Gram (−) bacteria.'

Cell recognition and adhesion occur due to biochemicals of cell membranes named

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. Proteins

  2. Lipids

  3. Proteins and lipids

  4. Glycoproteins and glycolipids

Show answer
Correct Option: D
Explanation:
  • Cell recognition and adhesion occur due to biochemicals of cell membranes name glycoproteins and glycolipids.
  • Glycocalyx or pericellular matrix is a carbohydrate-enriched coating of glycoprotein and a glycolipid that covers the cell membranes of few bacteria, epithelial cells and other cells. 
  • It is mainly used in the recognition of the cell (distinguish between healthy and diseased cells) and also regulates the endothelial vascular tissues.
  • So, the correct answer is 'Glycoproteins and glycolipids'.

Peptidoglycan (mucopeptide) is found in walls of _____________.

botany option b: biotechnology and bioinformatics gram staining microbiology: organisms in industry cell wall and cell membrane

  1. Only Gram  +ve bacteria

  2. Both Gram +ve and -ve bacteria

  3. Gram +ve, -ve bacteria and fungi

  4. Bacteria and green algae

Show answer
Correct Option: B
Explanation:

The mucopeptide is a peptidoglycan that is insoluble in nature. It is also called as murein. It is present in almost all bacterial cell walls.