NEET Practice Questions (MCQs) with Answers & Solutions

(b) Heroin is acyl derivative of morphine.

Heroin is an opioid drug made from morphine, a natural substance taken from the seed pod of the various opium poppy plants grown in Southeast and Southwest Asia, Mexico, and Colombia. Heroin can be a white or brown powder, or a black sticky substance known as black tar heroin. Other common names for heroin include big H, horse, hell dust,and smack.

What are the effects of heroin?

Heroin enters the brain rapidly and binds to opioid receptors on cells located in many areas, especially those involved in feelings of pain and pleasure and in controlling heart rate, sleeping, and breathing.

(c) It (C₁₇H₂₁O₄N) s an alkaloid, a local anaesthetic but dangerous habit forming drug.

(c) It is a fact.

A placebo (/pləˈsiːboÊŠ/ plÉ™-SEE-boh) is an inert substance or treatment which is not designed to have a therapeutic value.^[1]Common placebos include inert tablets (like sugar pills), inert injections (like saline), sham surgery,^[2] and other procedures.^[3]

In drug testing and medical research, a placebo can be made to resemble an active medication or therapy so that it functions as a control; this is to prevent the recipient(s) or others from knowing (with their consent) whether a treatment is active or inactive, as expectations about efficacy can influence results.^[4][5] In a clinical trial any change in the placebo arm is known as the placebo response, and the difference between this and the result of no treatment is the placebo effect.^[6]

A placebo may be given to a person in a clinical context in order to deceive the recipient into thinking that it is an active treatment. The use of placebos as treatment in clinical medicine is ethically problematic as it introduces deception and dishonesty into the doctor–patient relationship.^[7]

^{Placebos are typically inert tablets, such as sugar pills.}

(a) An antibiotic for cure of TB.

Streptomycin is an aminoglycoside antibiotic produced by the soil actinomycete Streptomyces griseus. It acts by binding to the 30S ribosomal subunit of susceptible organisms and disrupting the initiation and elongation steps in protein synthesis. It is bactericidal due to effects that are not fully understood.

C₂₁H₃₉N₇O₁₂

2,4-diguanidino-3,5,6-trihydroxycyclohexyl 5-deoxy-2-O-(2-deoxy-2-methylamino-alpha-L-glucopyranosyl)-3-C-formyl-beta-L-lyxopentanofuranoside

(a) Antiseptic drugs cause destruction of microorganisms that produce septic diseases, e.g.,dettol, savlon, acriflavine, boric acid, phenol, iodoform, KMnO₄ and some dyes such as chloramine-T, methylene blue, gentian violet.

(a) Lindane or gammexane is $\mathrm{\gamma }$-isomer of BHC.

(b)

Basic dyes contain NH₂ or -NR₂ group as colour bearing groups or colour enhancing groups. They are generally used for wool, cotton, leather, paper, polyester, nylon, etc., e.g. aniline yellow, chrysoidine G, Butter yellow, malachite green, etc.