Genetic Engineering and Biotechnology

Total Questions: 49

31. Which one of the following statements is not true with regard to the transplantation of stem cells in animals? [R.A.S/R.T.S. (Pre) 2007]

(a) They multiply themselves throughout the life span of an animal
(b) They repair the damaged tissues of the organs
(c) They have the capacity to produce one or more types of specialized cells
(d) They are found only in the embryo

Correct Answer: (d) They are found only in the embryo

Solution:Based on the cell type/tissue of origin, stem cells are classified as ‘Somatic Stem Cells’ (SSCs) and ‘Embryonic Stem Cells’ (ESCs). SSCs could be obtained from different sources, for example, the fetus, umbilical cord, placenta, infant, child or adult; and from different organs/tissues, while ESCs are derived from pre-implantation embryos (blastocysts). The derivation of human embryonic stem cells currently requires the destruction of ex utero embryos. The stem cells can regenerate themselves in vitro virtually forever. Indian research centres also created a few cell lines which can be developed into many types of tissues.

32. Which one of the following is the bioethically non-controversial source of stem cells as an alternative to the highly controversial embryonic stem cells? [U.P.P.C.S. (Pre) 2008]

(a) Bone marrow-derived stem cells
(b) Amniotic fluid-derived stem cells
(c) Blood of foetus
(d) Blood of babies

Correct Answer: (a) Bone marrow-derived stem cells

Solution:Stem cells are undifferentiated biological cells that can differentiate into specialized cells and can divide (through mitosis) to produce more stem cells. They are found in multicellular organisms. There are three known accessible sources of autologous adult stem cells in humans: Bone marrow, which requires extraction by harvesting that is drilling into bone (typically the femur or iliac crest). This is an ultimate alternative to controversial embryonic stem cells. Adipose tissue (lipid cells), which requires extraction by liposuction. Blood, which requires extraction through apheresis, wherein blood is drawn from the donor (similar to a blood donation) and passed through a machine that extracts the stem cells and returns other portions of the blood to the donor.

33. Consider the following statements: [I.A.S. (Pre) 2020]

Genetic changes can be introduced in the cells that produce eggs or sperms of a prospective parent.
A person’s genome can be edited before birth at the early embryonic stage.
Human-induced pluripotent stem cells can be injected into the embryo of a pig.

Which of the statements given above is/are correct?

(a) 1 only
(b) 2 and 3 only
(c) 2 only
(d) 1, 2 and 3

Correct Answer: (d) 1, 2 and 3

Solution:By using the gene-editing tool CRISPR-Cas9, genetic changes can be introduced in the cells that produce eggs or sperms of a prospective parent, and a person’s genome can be edited before birth at the early embryonic stage. Researchers from the Oregon Health and Science University, USA along with colleagues in California, China and South Korea had demonstrated that by repairing a mutation in human embryos using CRISPR-Cas9. Further, researchers from Spain, China and Japan, etc. had shown that human induced pluripotent stem cells could be injected into the embryo of a pig (or mice, rats). In March, 2019 Japan changes its rules on implanting human cells into animals.

34. What is the application of Somatic Cell Nuclear Transfer Technology? [I.A.S. (Pre) 2017]

(a) Production of bioinsecticides
(b) Manufacture of biodegradable plastics
(c) Reproductive cloning of animals
(d) Production of organisms free of diseases

Correct Answer: (c) Reproductive cloning of animals

Solution:Somatic cell nuclear transfer (SCNT) can be used in embryonic stem cell research, or in regenerative medicine where it is sometimes referred to as ‘therapeutic cloning’. It can also be used as the first step in the process of reproductive cloning. The nucleus of the somatic cell is inserted into the enucleated (after removal of nucleus) egg cell.

35. Hybridoma technology is a new biotechnological approach for commercial production of: [I.A.S. (Pre) 2000]

(a) Monoclonal antibodies
(b) Interferon
(c) Antibiotics
(d) Alcohol

Correct Answer: (a) Monoclonal antibodies

Solution:Hybridoma technology is a technology of forming hybrid cell lines (called hybridomas) by fusing an antibody-producing B cell with a myeloma (B cell cancer) cell that is selected for its ability to grow in tissue culture and for its absence of antibody chain synthesis. The antibodies produced by the hybridoma are all of a single specificity and are therefore monoclonal antibodies (in contrast to polyclonal antibodies). The production of monoclonal antibodies was invented by César Milstein and Georges J. F. Köhler in 1975. They shared the Nobel Prize in 1984 for medicine and physiology with Niels Kaj Jerne, who made theoretical contributions to immunology.

36. The Plant Field Gene Bank at Banthara will: [U.P.P.C.S. (Pre) 2001, 2003]

(a) Preserve endangered varieties of plants
(b) Check piracy of bio-diversity
(c) Identify economically important wild plants
(d) Look after all the above

Correct Answer: (d) Look after all the above

Solution:The Plant Field Gene Bank at Banthara will secure the endangered plants, prevent the piracy of biological diversity and also recognise the economically important plants.

37. Consider the following statements: [I.A.S. (Pre) 2019]

According to the Indian Patents Act, a biological process to create seed can be patented in India.
In India, there is no Intellectual Property Appellate Board.
Plant varieties are not eligible to be patented in India.

Which of the statements given above is/are correct?

(a) 1 and 3 only
(b) 2 and 3 only
(c) 3 only
(d) 1, 2 and 3

Correct Answer: (c) 3 only

Solution:According to article 3 (j) of The Patents Act, 1970 (of India) “plants and animals in whole or any part thereof other than micro organisms but including seeds, varieties and species and essentially biological processes for production or propagation of plants and animals” are not inventions and not eligible to be patented in India. Hence, statement 1 is not correct while statement 3 is correct. Statement 2 is not correct because ‘Intellectual Property Appellate Board’, a quasi-judicial body, was constituted in India in September 1958 to decide the disputes under the Copyright Act, 1957. Another ‘Intellectual Property Appellate Board’ has been constituted on 15th September 2003 to hear appeals against the decisions of the Registrar under the Trade Marks Act, 1999 and the Geographical Indications of Goods (Registration and Protection) Act, 1999.

38. Insect-resistant cotton plants have been genetically engineered by inserting a gene from a/an: [I.A.S. (Pre) 2000]

(a) Virus
(b) Bacterium
(c) Insect
(d) Plant

Correct Answer: (b) Bacterium

Solution:Insect-resistant cotton plants have been genetically engineered by inserting a gene from a bacteria (Bacillus thuringiensis). Strains of Bacillus thuringiensis produces different toxins which are harmful to different insects. Such variety of cotton is commonly known as Bt. cotton. The American multinational company Monsanto has produced such variety.

39. The American multinational company, Monsanto, has produced an insect-resistant cotton variety that is undergoing field trials in India. A toxin gene from which one of the following bacteria has been transferred to this transgenic cotton? [I.A.S. (Pre) 2001]

(a) Bacillus subtilis
(b) Bacillus thuringiensis
(c) Bacillus amyloliquafaciens
(d) Bacillus globii

Correct Answer: (b) Bacillus thuringiensis

40. The micro-organism which is associated with the production of Bt cotton is [U.P.P.C.S. (Pre) 2010]

(a) Fungus
(b) Bacterium
(c) Blue-green algae
(d) Virus