Assistant Professor in Pharmacy (Medical Education) 2023 — Kerala PSC PYQ Practice with Answers

Correct answer (Option B):\nThe modified Born-Trager's test is specifically used for the detection of C-glycosides such as aloin found in Aloe species. While the standard Born-Trager's test detects free anthraquinones or O-glycosides, C-glycosides require ferric chloride to break the carbon-carbon bond before oxidation can occur. Option B is correct.\n\nWhy others are wrong:\nOption A refers to O-glycosides, which give a positive result in the standard Born-Trager's test rather than the modified version. Options C and D refer to N-glycosides and S-glycosides respectively, which possess different structural linkages that do not respond to this anthraquinone specific chemical test.\n\nStudy tip:\nAloe contains aloin, which is a C-glycoside resistant to normal acid hydrolysis, hence requiring the strong oxidative cleavage provided by ferric chloride in the modified test.

Correct answer (Option D):\nCatechu is used as an anti-hypertensive crude drug due to its rich content of polyphenols and flavonoids like catechin, which exert significant cardiovascular protective and vasorelaxant properties. Option D is correct.\n\nWhy others are wrong:\nOption A is wrong because Opium is an analgesic and narcotic sedative. Option B is wrong because Belladonna is an anticholinergic drug that increases heart rate. Option C is wrong because Ephedra contains ephedrine, which acts as a sympathomimetic and increases blood pressure.\n\nRemember:\nCatechu belongs to the family Leguminosae and is traditionally employed for its astringent properties alongside its cardiovascular benefits.

Correct answer (Option C):\nThe mitotic index is the parameter used to evaluate the relative contribution of cell aggregates and individual free cells during growth in a culture medium. It measures the ratio between the number of cells undergoing mitosis and the total number of cells, reflecting active cellular proliferation. Option C is correct.\n\nWhy others are wrong:\nOption A is wrong because cell viability only indicates the percentage of living cells, not their proliferation dynamics. Option B is wrong because packed cell volume assesses total biomass accumulation without distinguishing the growth division behavior of clusters versus free individual entities.\n\nStudy tip:\nMitotic index calculations are crucial in plant and animal tissue culture to chart growth kinetics and optimize harvesting times.

Correct answer (Option B):\nAbrus precatorius is commonly known as Indian liquorice or Jequirity. Its roots are used as a substitute for true liquorice because they contain a sweet substance resembling glycyrrhizin, although its seeds are highly toxic due to the presence of abrin. Option B is correct.\n\nWhy others are wrong:\nOption A is wrong because Glycyrrhiza glabra is the botanical source of true liquorice (also called English or Spanish liquorice). Options C and D are completely distinct wild varieties belonging to the Fabaceae family that do not represent Indian liquorice.\n\nRemember:\nAbrus precatorius seeds are bright scarlet with a black spot and are historically used as weighing units (Ratti) in India.

Correct answer (Option A):\nThe biolistic method (or gene gun technique) is generally not suitable for protoplasts because the high-velocity microparticles can easily puncture, disintegrate, or kill the fragile, wall-less protoplasts. It is primary intended for intact plant cells with thick walls. Option A is correct.\n\nWhy others are wrong:\nOption B is wrong because electroporation works excellently on protoplasts by creating transient pores in the exposed plasma membrane. Option C is wrong because chemical agents like PEG easily induce DNA uptake in protoplasts. Option D is wrong because microinjection can handle delicate cellular membranes with micro-needles.\n\nStudy tip:\nProtoplasts require gentle physical or chemical methods like PEG-mediated transformation or electroporation because they lack a protective outer cell wall.