Question

True or False? An antimicrobial drug with a therapeutic index of 100 would be have a higher selective toxicity than a drug with an therapeutic index of 5.

True?

True or False? Transduction is a type of horizontal gene transfer that involves the uptake of naked (extracellular) DNA by a competent recipient cell.

True?

True or False? Oxygenic photosynthesis uses water as an electron donor, while anoxygenic photosynthesis uses other molecules (e.g. H2S) as electron donors; however, both processes generate ATP by way of oxidative phosphorylation using a cyclic electron transport chain and production of a proton motive force

False?

Please check if these are correct

Answer 1

Ans. #1. True. Higher is the TI value of a drug, greater is its safety profile and lesser is its toxicity towards the host cells.

So, the antimicrobial drug with TI value of 100 has a higher selective toxicity towards the target pathogen but lower toxicity towards the host cells than that of a drug with TI value of 5 (which has lower selective toxicity toward target pathogen and higher toxicity towards host cell).

#2. False.

Transduction: The process of transfer of DNA from one to another cell being mediated by a virus.

Transfection: The process of transfer of naked DNA into a target cell (say, bacterial, animal or plant cell) by artificial methods (say, using gene gun) is called transfection.

Transformation: A naked DNA is naturally taken up by the cell without mediation of any viral agent or artificial methods.

#3. False. The first part of statement- oxygenic photosynthesis uses H₂O as electron donor whereas anoxygenic photosynthesis uses H₂S as electron donor- is true. However, the formation of ATP during photosynthesis is called photophosphorylation whereas the term oxidative phosphorylation refer to ATP production in mitochondria during cellular respiration. Moreover, oxygenic phosphorylation involves both cyclic and non-cyclic electron flow whereas anoxygenic photosynthesis uses only cyclic electron flow during photophosphorylation.