Read the following paragraph carefully and answer the given questions.
Certain types of leukocytes (WBC) of our body like polymorpho-nuclear leukocytes (PMNL-neutrophils) and monocytes and natural killer (type of lymphocytes) in the blood as well as macrophages in tissues can phagocytose and destroy microbes. For determining the cause of allergy, the patient is exposed to or injected with very small doses of possible allergens, and the reactions studied. The use of drugs like anti-histamine, adrenalin and steroids quickly reduce the symptoms of allergy. Heroin, commonly called smack is chemically diacetylmorphine which is a white, odourless, bitter crystalline compound. This is obtained by acetylation of morphine. Techniques like radiography (use of X-rays), CT (computed tomography) and MRI (magnetic resonance imaging) are very useful to detect cancers of the internal organs. Different species of Plasmodium (P. vivax, P. malaria and P. falciparum) are responsible for different types of malaria. Of these, malignant malaria caused by Plasmodium falciparum is the most serious one and can even be fatal.
Heroin, commonly called smack is chemically ______ which is a white, odourless, bitter crystalline compound.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Diacetylmorphine
Heroin is an opioid, a drug that binds to opioid receptors in the central nervous system and the gut. It is made from morphine by acetylation, that is, by adding acetyl groups. Two acetyl groups are added, so its chemical name is di-acetyl-morphine.
Option (1) Diacylmorphine — Incorrect. This is not the chemical name of heroin. The name of heroin carries “acetyl”, because heroin comes from the acetylation of morphine.
Option (2) Diacetylmorphate — Incorrect. This is not the chemical name of heroin either. The parent compound is morphine, and the name keeps it as it is.
Option (3) Diacetylmorphane — Incorrect. Here too the last part of the word is changed. Heroin is made from morphine, not from any “morphane”.
Option (4) Diacetylmorphine — Correct. Heroin, commonly called smack, is diacetylmorphine, a white, odourless, bitter crystalline compound. It is a depressant and slows down body functions. NTA changed only a few letters at the end of one long word to make three options. Read every letter of a chemical name before you mark the answer.
Note 1: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.
Note 2: A similar question was also asked in CUET (UG) 2025 on 30-05-2025 (Slot 1).