Advanced Biotech Miscellaneous
- Match the items in groupl with the terms given in group 2
Group 1 Group 2 P. Lactobacillus and Bifidobacteria 1. Prebiotics Q. Polychlorobenzenes 2. Probiotics (PCBs) R. Fructo-oligosaccharides 3. Antibiotics S. β-Lactams 4. Xenobiotics
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⚈ Probiotics are live bacteria that may confer a health benefit on the host. Lactic acid bacteria (LAB) and bifidobacteria are the most common types of microbes used as probiotics.
⚈ A xenobiotic is a chemical which is found in an organism but which is not normally produced or expected to be present in it. The term xenobiotics is very often used in the context of pollutants such as dioxins and polychlorinated biphenyls.
⚈ Fructo-oligosaccharide (FOS) and lactulose have been classified as prebiotics. Prebiotics are non-digestible food ingredients that stimulate the growth and/or activity of bacteria in the digestive system in ways claimed to be beneficial to health.
⚈ β-Lactam antibiotics (beta-lactam antibiotics) are a broad class of antibiotics, consisting of all antibiotic agents that contains a β-lactam ring in their molecular structures.
Correct Option: A
⚈ Probiotics are live bacteria that may confer a health benefit on the host. Lactic acid bacteria (LAB) and bifidobacteria are the most common types of microbes used as probiotics.
⚈ A xenobiotic is a chemical which is found in an organism but which is not normally produced or expected to be present in it. The term xenobiotics is very often used in the context of pollutants such as dioxins and polychlorinated biphenyls.
⚈ Fructo-oligosaccharide (FOS) and lactulose have been classified as prebiotics. Prebiotics are non-digestible food ingredients that stimulate the growth and/or activity of bacteria in the digestive system in ways claimed to be beneficial to health.
⚈ β-Lactam antibiotics (beta-lactam antibiotics) are a broad class of antibiotics, consisting of all antibiotic agents that contains a β-lactam ring in their molecular structures.
- Which of the following statements are true with respect to a special complex called ‘dicer’?
(P) It consists of deoxyribonuclease and DNA fragments
(Q) It consists of ribonuclease and RNA fragments
(R) It is involved in gene silencing
(S) It triggers apoptosis
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⚈ Dicer is an endoribonuclease in the RNase III family that cleaves double-stranded RNA (dsRNA) and pre-microRNA (miRNA) into short double-stranded RNA fragments about 20-25 base pairs long, with a two-base overhang on the 3’ end. Dicer contains two RNase III domains and one PAZ domain; the distance between these two regions of the molecule is determined by the length and angle of the connector helix and influences the length of the siRNAs it produces.
⚈ Dicer facilitates the formation of the RNA-induced silencing complex (RISC), whose catalytic component argonaute is an endonuclease capable of degrading messenger RNA (mRNA).Correct Option: B
⚈ Dicer is an endoribonuclease in the RNase III family that cleaves double-stranded RNA (dsRNA) and pre-microRNA (miRNA) into short double-stranded RNA fragments about 20-25 base pairs long, with a two-base overhang on the 3’ end. Dicer contains two RNase III domains and one PAZ domain; the distance between these two regions of the molecule is determined by the length and angle of the connector helix and influences the length of the siRNAs it produces.
⚈ Dicer facilitates the formation of the RNA-induced silencing complex (RISC), whose catalytic component argonaute is an endonuclease capable of degrading messenger RNA (mRNA).
- Determine the correctness or otherwise of following Assertion [a] and Reason [r]
Assertion : The enzymatic degradation of cell wall to obtain single cell called protoplast has helped immensely in developing somatic cell genetics in plants
Reason : In plants or animals, fusion to two cells must occur through the plasma membrane
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Somatic fusion, also called protoplast fusion through plasma membrane, is a type of genetic modification in plants by which two distinct species of plants are fused together to form a new hybrid plant with the characteristics of both, a somatic hybrid. Hybrids have been produced either between the different varieties of the same species (e.g. between non-flowering potato plants and flowering potato plants) or between two different species (e.g. between wheat triticum and rye secale to produce Triticale).
Correct Option: B
Somatic fusion, also called protoplast fusion through plasma membrane, is a type of genetic modification in plants by which two distinct species of plants are fused together to form a new hybrid plant with the characteristics of both, a somatic hybrid. Hybrids have been produced either between the different varieties of the same species (e.g. between non-flowering potato plants and flowering potato plants) or between two different species (e.g. between wheat triticum and rye secale to produce Triticale).
- Which of the following statements are true about glyphosate tolerant transgenic plants?
P. Transgenic plants detoxify glyphosate.
Q. Transgenic plants produce an altered enzyme that is not affected by glyphosate.
R. Transgenic plants sequester glyphosate in vacuoles.
S. Transgenic plants overcome the inhibition of aromatic amino acid biosynthesis.
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Statement Q :When glyphosphate expressed in chloroplasts of transgenic plants, the insensitive enzymes produced by confer tolerance to the herbicide glyphosphate.
Statement S : Glyphosphate acts by inhibiting enolpyruvyl-shikimate-3-phosphate synthase (EPSPS), an enzyme in the pathway leading to biosynthesis of aromatic amino acids. Since transgenic plants exhibit resistance to glyphosphate, there is no inhibition of the synthesis of aromatic amino acids.Correct Option: C
Statement Q :When glyphosphate expressed in chloroplasts of transgenic plants, the insensitive enzymes produced by confer tolerance to the herbicide glyphosphate.
Statement S : Glyphosphate acts by inhibiting enolpyruvyl-shikimate-3-phosphate synthase (EPSPS), an enzyme in the pathway leading to biosynthesis of aromatic amino acids. Since transgenic plants exhibit resistance to glyphosphate, there is no inhibition of the synthesis of aromatic amino acids.
- Which of the following statements hold true for pluripotent stem cells (PSCs) under in vitro conditions?
P. PSCs can be maintained in an undifferentiated state
Q. PSCs exhibit abnormal and unstable karyotypes
R. PSCs can differentiate into a wide variety of cell types
S. PSCs cannot be passaged continuously
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In cell biology, pluripotency (from the Latin plurimus, meaning very many, and potens, meaning having power) refers to a stem cell that has the potential to differentiate into any of the three germ layers: endoderm (interior stomach lining, gastrointestinal tract, the lungs), mesoderm (muscle, bone, blood, urogenital), or ectoderm (epidermal tissues and nervous system). Pluripotent stem cells can give rise to any fetal or adult cell type. However, alone they cannot develop into a fetal or adult organism because they lack the potential to contribute to extraembryonic tissue, such as the placenta.
Correct Option: B
In cell biology, pluripotency (from the Latin plurimus, meaning very many, and potens, meaning having power) refers to a stem cell that has the potential to differentiate into any of the three germ layers: endoderm (interior stomach lining, gastrointestinal tract, the lungs), mesoderm (muscle, bone, blood, urogenital), or ectoderm (epidermal tissues and nervous system). Pluripotent stem cells can give rise to any fetal or adult cell type. However, alone they cannot develop into a fetal or adult organism because they lack the potential to contribute to extraembryonic tissue, such as the placenta.
