20 NEET questions on Biotechnology and its Applications. A sample is shown below with full explanations; the rest are available free after signing up.
Streptokinase, produced by Streptococcus and improved by genetic engineering, dissolves clots in the blood vessels of patients who have had a myocardial infarction. Penicillin is an antibiotic, cyclosporin A an immunosuppressant used in transplants, and statins lower blood cholesterol.
Source: NEET 2026 re-exam (21 June), Code 50, Q136
Bacillus thuringiensis stores the toxin as inactive crystalline protoxin, which is why the bacterium itself is unharmed. Once eaten, the alkaline pH of the insect midgut dissolves the crystals and releases the active toxin — a mechanism that also explains why the toxin is harmless in the acidic human stomach.
Source: NEET 2026 re-exam (21 June), Code 50, Q137
In 1983 Eli Lilly produced the two insulin chains A and B separately in genetically engineered Escherichia coli, a bacterium, and then combined them by creating disulphide bonds to give humulin. This removed the need to extract insulin from slaughtered cattle and pigs, whose insulin caused allergic reactions in some patients.
Source: NEET 2025 (4 May), Code 45, Q116