Tag: biology

Quizzes (1160) Questions (12174)

Questions Related to biology

Multiple choice biotechnology and genetic engineering genetic technology genetic engineering biology making use of enzymes

Transgenic plants are developed by

  1. clone and genetically modified genes

  2. introduction of foreign genes

  3. genetic engineering

  4. purified genes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Transgenic plants are organisms that have had their genetic material altered by the introduction of foreign genes from another species using genetic engineering techniques.

Multiple choice biotechnology and genetic engineering genetic technology genetic engineering biology making use of enzymes

Bacillus thuringiensis (Bt) strains have been used for designing novel

  1. bio-fertilizers

  2. bio-metallurgical techniques

  3. bio-mineralization processes

  4. bio-insecticidal plants
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Bacillus thuringiensis (Bt) produces proteins that are toxic to specific insect pests, which is why it is used to create bio-insecticidal crops.

Multiple choice biotechnology and genetic engineering genetic technology genetic engineering biology making use of enzymes

Which of the following is not a correct statement?

  1. "Bt" in "Bt-cotton" indicates that it is a genetically modified organism produced through biotechnology

  2. Somatic hybridization involves fusion of two complete plant cells carrying desired genes

  3. The anti-coagulant hirudin is being produced from transgenic Brassica napus seed

  4. "Flavr Savr" variety of tomato has enhanced the Production of ethylene which improves its taste
Reveal answer Fill a bubble to check yourself
A,B,D Correct answer
Multiple choice biotechnology and genetic engineering genetic technology genetic engineering biology making use of enzymes

Human insulin is being commercially produced from a transgenic species of

  1. Mycobacterium

  2. Rhizobium

  3. Saccharomyces

  4. Escherichia
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A transgenic microorganism is a microbe, usually a bacterium, into which genetic information has been introduced from the outside and which possesses the ability to pass that information on to subsequent generations. In this process by which, scientists introduce new genetic material into a microorganism is called as molecular or gene cloning. It involves the isolation of DNA from a source other than the microorganism itself. The human insulin is produced by genetically engineered Escherichia coli.

Thus, the correct answer is option D. 

Multiple choice biotechnology and genetic engineering genetic technology genetic engineering biology making use of enzymes

When using bacteria to clone a human gene and express its product-as in the case of insulin-the gene cannot contain introns because bacteria do not have the enzymes to process mRNA. Therefore

  1. if the sequence is known, very small human genes can be built with a DNA synthesizer in a laboratory and they will lack introns

  2. reverse transcriptase can be used to make DNA backwards from human mature mRNA and this would lack introns

  3. it is impossible to use bacteria to express human gene products because all human genes have introns

  4. both (a) and (b) are true
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In order for a human gene to be expressed in bacteria, it must have one important modification. Specifically, it must lack introns. Introns are intervening sequences found in many human genes, and they are removed from eukaryotic RNA transcripts by splicing to make a mature mRNA. Bacteria lack enzymes for splicing. This problem is tackled by using the following approaches:- 

  1. Reverse transcriptase is used to make DNA backwards from human mature mRNA. This DNA will lack introns and DNA will contain only those genes that are going to be expressed. 
  2. Artificial gene synthesis by building polynucleotide chain based on the sequence of nucleotides in DNA fragment of the gene of interest. 

So, the correct option is 'both (a) and (b) are true'. 

Multiple choice biotechnology and genetic engineering genetic technology genetic engineering biology making use of enzymes

Some of the steps involved in the production of humilin are given below. Arrange them in the correct sequence and select the correct option.
(i) Synthesis of gene (DNA) for human insulin artificially
(ii) Culturing recombinant E.coll in bioreactors 
(iii) Purification of humilin
(iv) Insertion of human insulin gene into plasmid
(v) Introduction of recombinant plasmid into E.coli 
(vi) Extraction of recombinant gene product from E.coli.

  1. (ii), (i), (iv), (iii), (v), (vi)

  2. (i), (iii), (v), (vi), (ii), (iv)

  3. (i), (iv), (v), (ii), (vi), (iii)

  4. (iii), (v), (ii), (i), (vi), (iv)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The given sentences can be arranged in a systemic order of i, iv, v, ii, vi, iii.

So, the correct option is '(i), (iv), (v), (ii), (vi), (iii)'.

Multiple choice biotechnology and genetic engineering genetic technology genetic engineering biology making use of enzymes

Which of the following is produced by genetic engineered bacteria?

  1. thyroxine

  2. insulin

  3. glucagon

  4. ADH
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Genetically modified or Genetically engineered bacteria were the first organisms to be modified in the laboratory, due to their simple genetics. These organisms are now used for several purposes and are particularly important in producing large amounts of pure human proteins for use in medicine. Insulin is normally produced by it.

So, the correct option is 'insulin'.

Multiple choice biotechnology and genetic engineering genetic technology genetic engineering biology making use of enzymes

During the processing of the prohormone "proinsulin" into the mature "insulin".

  1. C-peptide is added to proinsulin

  2. C-peptide is removed from proinsulin

  3. B-peptide is added to proinsulin

  4. B-peptide is removed from proinsulin
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Both C-Peptide and mature insulin are biologically active. Cell components and proteins in this image are not to scale. Proinsulin is the prohormone precursor to insulin made in the beta cells of the islets of Langerhans, specialized regions of the pancreas. In humans, proinsulin is encoded by the INS gene.

So, the correct option is 'C-Peptide is removed from proinsulin'.