Tag: option b: biotechnology and bioinformatics

Questions Related to option b: biotechnology and bioinformatics

Arrange the following steps in a correct sequence as per Gram's staining technique:

Treatment with $0.5$% iodine solution $(1)$, washing with water $(2)$, treatment with absolute alcohol/ acetone $(3)$, staining with weak alkaline solution of crystal violet $(4)$.

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

  1. $4\rightarrow 1 \rightarrow 2\rightarrow 3$

  2. $3\rightarrow 2 \rightarrow 1\rightarrow 4$

  3. $3\rightarrow 1 \rightarrow 2\rightarrow 4$

  4. $4\rightarrow 2 \rightarrow 3\rightarrow 1$

Show answer
Correct Option: A
Explanation:

Bacteria can be classified into two groups based upon reaction of bacteria to Gram's stain (Christian Gram, $1884$). Bacteria are first stained with weakly alkaline solution of crystal violet and then treated with $0.5$% iodine solution. This is followed by washing with water and then with alcohol or acetone. Bacteria which retain blue or purple colour are known as Gram $(+)$ bacteria (e.g., Bacillus subtilis). Bacteria which do not retain stain and become colourless are called Gram $(-)$ bacteria (e.g., Escherichia coli). Washing of the stain in Gram $(-ve)$ bacteria is due to high lipid content of their cell wall which gets dissolved in organic solvents like acetone.

So, the correct answer is '$4\rightarrow 1 \rightarrow 2\rightarrow 3$'.

Select the correct option:

Which of the given statements are correct?
(i) Bacillus subtilis is a Gram $(+)$ bacteria.
(ii) Escherichia coli is a Gram $(-)$ bacteria.
(iii) Washing of the Gram's stain in Gram $(-)$ bacteria is due to high lipid content of the cell wall, which gets dissolved in organic solvent like acetone.

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

  1. (i) and (ii)

  2. (ii) and (iii)

  3. (i) and (iii)

  4. (i), (ii) and (iii)

Show answer
Correct Option: D
Explanation:

Bacteria can be classified into two groups based upon reaction of bacteria to Gram's stain (Christian Gram, $1884$). Bacteria are first stained with weakly alkaline solution of crystal violet and then treated with $0.5$% iodine solution. This is followed by washing with water and then with alcohol or acetone. 

Bacteria which retain blue or purple colour are known as Gram $(+)$ bacteria (e.g., Bacillus subtilis). 
Bacteria which do not retain stain and become colourless are called Gram $(-)$ bacteria (e.g., Escherichia coli). Washing of the stain in Gram $(-ve)$ bacteria is due to high lipid content of their cell wall which gets dissolved in organic solvents like acetone.
So, the correct answer is '(i), (ii) and (iii)'.

Glycocalyx (mucilage sheath) of a bacterial cell may occur in the form of a loose sheath called _____ or it may be thick and tough called _____.

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

  1. Capsule, Slime layer

  2. Slime layer, Capsule

  3. Mesosome, Capsule

  4. Mesosome, Slime layer

Show answer
Correct Option: B
Explanation:

Glycocalyx (mucilage sheath) is the outermost layer of the bacterial cell envelope which consists of non-cellulosic polysaccharides with or without proteins. It may occur in the form of loose sheath, called slime layer. If it is a thick covering, it is called capsule. Glycocalyx gives sticky character to the cell and is not absolutely essential for survival of bacteria. It prevents desiccating, protects from phagocytes, toxic chemicals and viruses and serves in attachment. It may give selective advantage through in certain situations.

So, the correct answer is 'Slime layer, capsule'.

Which stain is used the microbe present in the fresh butter milk?

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

  1. Methylene blue

  2. Safranin

  3. Iodine

  4. Eosin

Show answer
Correct Option: C
Explanation:

a quick version of buttermilk, known as acidified buttermilk, is used to make paneer. The tartness of buttermilk is due to acid in milk, where iodine is suitable.

So, the correct option is 'Iodine'.

'Glycocalyx' is a term used for thin layer of

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

  1. Lipoproteins

  2. Phosphoproteins

  3. Glycoproteins

  4. Phospholipids

Show answer
Correct Option: C
Explanation:

The glycocalyx is a glycoprotein-polysaccharide covering that surrounds the cell membranes of some bacteria, epithelia and other cells. The glycocalyx is a type of identifier that the body uses to distinguish between its own healthy cells and transplanted tissues, diseased cells, or invading organisms. 
Thus, the correct answer is option C.

Use of transgenic plants as biological factories for the production of special chemicals is called as

biology option b: biotechnology and bioinformatics pcr cutting, insertion and ligation of dna gene cloning procedure

  1. Molecular farming

  2. Molecular genetics

  3. Molecular mapping

  4. Dry farming

Show answer
Correct Option: A
Explanation:
Molecular genetics is the study of structure and function of gene and regulation of its expression. It includes isolation and characterization of genes and identification of regulatory sequences. 
Molecular farming is transfer of genes of industrial importance to plants and animals for production of chemicals, for example production of transgenic animals for increased milk production. 
Molecular mapping is identification of loci of genes and their relative distance on chromosomes; DNA finger printing and genomic imprinting are most common techniques used for the purpose. 
Dry farming refers to crop production without irrigation, i.e., under limited moisture conditions; it is practiced for dry lands where water availability is low. 

Desired genes have been introduced into transgenic animals to obtain large-scale production of useful biological products encoded by these genes. This approach is generally referred to as _____________.

biology option b: biotechnology and bioinformatics pcr cutting, insertion and ligation of dna gene cloning procedure

  1. Hybridoma technology

  2. Molecular farming

  3. Gene therapyx

  4. Downstream processing

Show answer
Correct Option: B

A set of genes of cDNA is immobilized on a glass slide and used in transcriptome studies is called 

biology option b: biotechnology and bioinformatics pcr cutting, insertion and ligation of dna gene cloning procedure

  1. Proteome

  2. Microarray

  3. DNA chip

  4. Genome

Show answer
Correct Option: B
Explanation:

The transcriptome is the sum of all of its RNA transcripts. The information content of an organism is recorded in the DNA of its genome and expressed through transcription. A microarray is a laboratory tool used to detect the expression of thousands of genes at the same time. DNA microarray is microscopic glass slides that are printed with thousands of tiny spots in defined positions with each spot containing a known cDNA. The cDNA is made immobilized on a glass slide.

So, the correct answer is 'Microarray'.

Recently government of India has allowed mixing of alcohol in petrol. What is amount of alcohol permitted for mixing in petrol?

biology option b: biotechnology and bioinformatics pcr cutting, insertion and ligation of dna gene cloning procedure

  1. $25\%$

  2. $10-15\%$

  3. $10\%$

  4. $5\%$

Show answer
Correct Option: D
Explanation:

The amount is 5%.

Correct answer-D

A probe which is a molecule used to locate specific sequences in a mixture of DNA or RNA molecules could be __________________.

biology option b: biotechnology and bioinformatics pcr cutting, insertion and ligation of dna gene cloning procedure

  1. A single stranded RNA

  2. A single stranded DNA

  3. Either RNA or DNA

  4. Can be ssDNA but not ssRNA

Show answer
Correct Option: B
Explanation:

The molecular probes are usually single-stranded places of DNA (sometimes RNAs) labeled with radioisotopes such as phosphorus- 32. Molecular probes are available for many genetic disorders such as Duchenne muscular dystrophy, cystic fibrosis, Tay-Sachs disease.