Biotechnology

Pusa Komal is a cowpea variety known for disease resistance (especially against bacterial blight), not insect pest resistance.
Other varieties like Pusa Gaurav, Sawani, and Sem 2 are bred for insect pest resistance.

Step 1: Matching Transgenic papaya (A).
Transgenic papaya was developed to resist Ringspot virus. A - II Step 2: Matching Bt - cotton (B).
Bt cotton is engineered to produce an insecticidal protein (Bt toxin) effective against pests. B - IV Step 3: Matching Roundup Ready soybean (C).
This variety is genetically modified for herbicide resistance (glyphosate). C - I Step 4: Matching Transgenic Tomato (D).
Transgenic tomatoes were developed with resistance to Pseudomonas. D - V

\textit{Bacillus thuringiensis} (Bt) produces insecticidal proteins known as Cry proteins. These are toxic to certain insect larvae.
cry IAb is the specific Bt gene effective against corn borers, making it the correct answer.

Statement I: Correct. The Genetic Engineering Appraisal Committee (GEAC) approves GMO research.
Statement II: Correct. Molecular farming uses genetically modified plants to produce pharmaceuticals and industrial compounds.
Statement III: Incorrect. Basmati rice is not a genetically modified or transgenic crop.
Statement IV: Correct. “Flavr Savr” tomato is engineered for longer shelf life.

Let's match each item in List-A with the appropriate term from List-B: \begin{itemize} \item A. Forensic science → IV. DNA fingerprinting DNA fingerprinting is a core technique used in forensic science for identifying individuals. \item B. Antigen-antibody interaction → III. ELISA ELISA (Enzyme-Linked Immunosorbent Assay) is used to detect antigen-antibody interactions. \item C. Detection of HIV → II. PCR PCR (Polymerase Chain Reaction) is used to amplify and detect viral genetic material, including HIV. \item D. Gene insertion into cells to treat disease → I. Gene therapy Gene therapy involves inserting functional genes into a patient's cells to treat genetic disorders. \end{itemize} So the correct match is: A–IV, B–III, C–II, D–I

Statement I: Ribonuclease and proteases remove RNA and proteins respectively, allowing pure DNA isolation.
Statement II: Ethidium bromide binds to DNA and fluoresces under UV light, making DNA visible in gel electrophoresis.
Statement III: Restriction enzymes create sticky ends, and DNA ligase joins the desired DNA fragments — enabling gene extraction. All three statements are correct.

Step 1: Define non-transformants.
Non-transformants are cells that have not taken up the foreign DNA during a transformation experiment. Step 2: Analyze the role of each option. (1) Restriction enzyme:
These cut DNA at specific sites but do not help identify transformed vs. non-transformed cells. (2) Antibiotic:
Antibiotics themselves are not used to identify cells. However, when linked to a resistance gene (marker), they allow for selection. (3) Selectable marker:
Correct answer. These genes (like antibiotic resistance genes) are inserted along with the gene of interest. When the cells are grown on antibiotic media, only transformed cells (with the marker) survive, helping in identification and elimination of non-transformants. (4) Plasmid:
Plasmids are vectors used to carry foreign genes but by themselves do not perform selection.

Understand each statement. Statement (1):
This is correct. Downstream processing refers to the series of operations involved in the purification and separation of a biotechnological product after the fermentation or cell culture process. Statement (2):
This is also correct. Bioreactors are used in industrial biotechnology for growing organisms under controlled conditions to produce enzymes, hormones, and other substances in large quantities. Statement (3):
This is correct. The most commonly used bioreactors are stirred tank bioreactors, which provide efficient mixing and aeration. Statement (4):
This is incorrect. Small volume cultures are typically used in labs for testing or small-scale research. They cannot yield appreciable or commercial-scale quantities of products. For industrial production, large volume cultures are required.

Statement I: Correct. Streptokinase is an enzyme produced by \textit{Streptococcus} and used as a clot buster.
Statement II: Correct. \textit{Saccharomyces cerevisiae} (yeast) is used for ethanol production in industries.
Statement III: Incorrect. Cyclosporin-A is an immunosuppressive drug, not a cholesterol-lowering agent, and is produced by \textit{Trichoderma polysporum}.
Statement IV: Correct. Statins, which lower cholesterol, are produced by yeast species like \textit{Monascus purpureus}.

Step 1: Understand the question.
The question asks to identify the correct statements regarding biofertilizers and microbial associations in plants. Step 2: Evaluate each statement. \begin{itemize} \item Statement I: The use of biofertilizers reduce the use of chemical fertilizers.
Biofertilizers are living microorganisms that improve soil fertility and plant growth by enhancing nutrient availability through processes like nitrogen fixation, phosphorus solubilization, and potassium mobilization. By doing so, they can effectively reduce the reliance on synthetic chemical fertilizers. This statement is Correct. \item Statement II: Mycorrhizae enhances phosphorous content in the soil.
Mycorrhizal fungi form a symbiotic relationship with plant roots. They extend their hyphae into the soil, greatly increasing the root's surface area for absorption. Their primary role concerning phosphorus is to solubilize insoluble forms of phosphorus in the soil, making it available for plant uptake, thereby enhancing phosphorus availability or uptake by the plant. They do not typically increase the total content of phosphorus in the soil, but rather make existing phosphorus more accessible. Due to the precise wording "enhances phosphorous content in the soil" (implying increasing the total amount), this statement is often considered Incorrect in a strict sense, as they facilitate uptake rather than directly adding content. \item Statement III: An important biofertilizer in legume crops is Rhizobium.
Rhizobium is a genus of bacteria that forms a symbiotic association with the roots of leguminous plants, leading to the formation of root nodules. Within these nodules, Rhizobium bacteria fix atmospheric nitrogen into ammonia, a form usable by plants. This process significantly contributes to the nitrogen nutrition of legume crops, making Rhizobium an important biofertilizer. This statement is Correct. \item Statement IV: Glomus forms mycorrhizal association with plants.
Glomus is a well-known genus of arbuscular mycorrhizal (AM) fungi. These fungi form endomycorrhizal associations with the roots of about 80% of terrestrial plant species, playing a crucial role in enhancing nutrient (especially phosphorus) uptake by the plants. This statement is Correct. \end{itemize} Step 3: Identify the correct option based on the evaluation.
Statements I, III, and IV are correct. Statement II is generally considered incorrect due to its precise wording. Therefore, the combination of correct statements is I, III, and IV. This matches option (4). The final answer is .