Tag: option b: biotechnology and bioinformatics

Questions Related to option b: biotechnology and bioinformatics

A culture of Mycobacterium leprae was subjected to alkaline ethanol extraction prior to acid-fast staining. The colour of the culture following staining will be

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

  1. Red

  2. Green

  3. Yellow

  4. Blue

Show answer
Correct Option: A
Explanation:
A culture of Mycobacterium leprae was subjected to alkaline ethanol extraction prior to acid-fast staining. The colour of the culture following staining will be red because it is an acid-fast bacteria as it contains a large amount of lipoidal material in their cell wall which prevents penetration of decolorizing solution.

So, the correct answer is 'Red'.

Gram positive bacteria are more rigid than Gram negative bacteria because of the 

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

  1. presence of multiple layers of peptidoglycan

  2. lack of D-amino acids in their cell wall

  3. presence of N-acetylgalactosamine in the peptidoglycan backbone

  4. presence of lipopolysaccharide

Show answer
Correct Option: A
Explanation:
Because gram-positive bacteria are surrounded by layers of peptidoglycan which is many times thicker than is found in the gram negatives. Gram-negative bacteria are surrounded by a thin peptidoglycan cell wall, which is surrounded by an outer membrane containing lipopolysaccharide which is not present in gram-positive bacteria.

So, the correct answer is 'presence of multiple layers of peptidoglycan'.

Mesosomes were taken as

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

  1. Golgi bodies

  2. Plastids

  3. Mitochondria

  4. Endoplasmic recticulum

Show answer
Correct Option: C
Explanation:

In the vesicle of mesosomes, the respiratory enzymes and the components of electron transport such as ATPase, dehydrogenase, cytochrome are present in low amount. So, they were considered anologous to mitochondria for their respiratory function. 

So, the correct option is 'Mitochondria'.

Which of the following statements is false?

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

  1. Bacteria glycocalyx differ in composition and thickness among diffrent bacteria.

  2. Bacterial envelope has a layered structure and each layer has a distinct function but they act as a single structure

  3. Bacteria are organelle less and contains ribosomes

  4. Number and arrangements of flagella is variable in bacteria.

Show answer
Correct Option: A

____________ is a microbial bio-control agent.

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

  1. Pseudomonas

  2. Penicillium

  3. Bacillus thuringiensis

  4. Clostridium

Show answer
Correct Option: A
Explanation:

Pseudomonas are aerobic, gram-negative bacteria, ubiquitous in agricultural soils, and are well adapted to growing in the rhizosphere. Pseudomonads possess many traits that make them well suited as biocontrol and growth-promoting agents. 

The large holes in "swiss-cheese" are due to production of large amount of $CO _2$ by a bacterium named?

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

  1. Lactobacillus

  2. Saccharomyces cerevisiae

  3. Propionibacterium sharmani

  4. Streptococcus

Show answer
Correct Option: A

Difference in Gram +ve  and Gram -ve bacteria is due to

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

  1. Cell wall

  2. Cell membrane

  3. Ribosome

  4. Cytoplasm

Show answer
Correct Option: A
Explanation:

The cell wall of certain bacteria shows a characteristic reaction to the stain devised by C. Gram. Those bacteria which retain the stain are known as Gram positive and those which do not retain the stain are called Gram negative.

  • The cell wall in bacteria contains peptidoglycan, a polymer of N-acetyl glucosamine, N-acetyl muramic acid and amino acids.
  • Gram-positive cell walls contain a thick layer of peptidoglycan that encircles the cell.
  • Gram-negative cell walls contain a thin layer of peptidoglycan between the cytoplasmic membrane and the outer membrane.

Bacterial cell wall is composed of peptidoglycan, a complex of oligosaccharides and proteins.        The oligosaccharide component consist of _________

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

  1. Linear chain of alternating NAG and NAM linked by ${\alpha}$ (1 -4) linkage

  2. Linear chains of alternating NAG and NAM linked by ${\beta}$ (1-4) linkage.

  3. Linear chain of glucose linked by $4{\beta}$ (1-4) linkage.

  4. Linear chain of glucose linked by ${\alpha}$ (1-4) linkage

Show answer
Correct Option: B
Explanation:

The oligosaccharide component of bacterial cell wall consists of linear chains of alternating NAG and NAM linked by ${\beta}$ (1-4)linkage.

Gram-negative bacteria that cause infections, when stained,  do not retain the crystal violet stain, which tells the researcher that

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

  1. The peptidoglycan layer is thick and the bacteria are resistant to antibiotics.

  2. The peptidoglycan layer is very thin and the bacteria is susceptible to antibiotics.

  3. The peptidoglycan layer is very thin and the bacteria are resistant to antibiotics.

  4. The peptidoglycan layer contains an impermeable lipid layer.

Show answer
Correct Option: C
Explanation:

The peptidoglycan layer of the gram negative bacteria are thin and are also referred to as the cell envelope. The layer is wavy and provides resistance to antibiotics. They are more virulent as compared to Gram positive bacteria

So, the correct answer is 'The peptidoglycan layer is very thin and the bacteria are resistant to antibiotics'

Cell organelles are the parts of a living cell. All cells have a cell membrane and some cells have a cell wall.
 Which of the following has a cell wall? 
 I. Plants
 II. Bacteria
 III. Fungi

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

  1. I only

  2. II only

  3. I and II only

  4. II and III only

  5. I, II and III

Show answer
Correct Option: E
Explanation:
  • Cell wall is the outermost, rigid, protective, non-living and supportive layer found in plant cells, bacteria, fungi, and some protists but absent in animal cells.

1. Plants cell wall is made up of cellulose, hemicellulose, and pectin. Cellulose is a polymer of glucose and pectin is a polymer of galactouronic acid.

2. Bacterial cell wall is made up of protein lipid polysaccharide NAG (N-Acetyl Glucosamine) and NAM (N-Acetyl Muramic Acid).

3. Fungal cell wall is made up of chitin which is a polymer of glucosamine.
Hence all options are correct.

So, the correct answer is 'I, II and III'.