Human Health and Diseases — Important Questions

Papaver somniferum (Poppy plant)

Step 1: Heroin (smack) is chemically diacetyl morphine — a white, odourless, bitter crystalline compound. Step 2: It is obtained by acetylation of morphine, which is extracted from the flowers of the poppy plant (Papaver somniferum). Step 3: Cannabis sativa (Hemp plant) is the source of cannabinoids like marijuana, ganja, and hashish. Step 4: Erythroxylum coca is the source of cocaine. Step 5: Atropa belladonna has hallucinogenic properties but is not the source of heroin. Therefore, Papaver somniferum (Poppy plant) is the correct answer.

Malignant tertian malaria; 36–48 hours

Step 1: There are four species of Plasmodium causing malaria. Step 2: P. falciparum causes Malignant tertian malaria (also called quotidian malaria) with an erythrocytic cycle of 36–48 hours. Step 3: P. vivax causes Benign tertian malaria with a 48-hour cycle. Step 4: P. malariae causes Quartan malaria with a 72-hour cycle. Step 5: P. ovale causes Mild tertian malaria with a 48-hour cycle. P. falciparum is the most dangerous species causing the malignant form.

Phlebotomus (Sand fly)

Step 1: Kala-azar is caused by the protozoan Leishmania donovani. Step 2: It is transmitted by the vector Phlebotomus, commonly known as the sand fly. Step 3: Xenopsylla cheopis (rat flea) is the vector for Bubonic Plague (Yersinia pestis). Step 4: Tsetse fly (Glossina sp.) transmits African Sleeping Sickness (Trypanosoma sp.). Step 5: Musca domestica (House fly) is the carrier for Amoebiasis. Hence, Phlebotomus (sand fly) is the correct vector for Kala-azar.

Sporozoites

Step 1: When a female Anopheles mosquito bites a human, it injects saliva along with the infective stage of Plasmodium. Step 2: This infective stage is called sporozoites, which are stored in the salivary glands of the mosquito. Step 3: Sporozoites then enter the hepatic (liver) cells where they undergo schizogony to produce merozoites. Step 4: Merozoites are released from the liver and infect RBCs. Step 5: Trophozoites develop inside RBCs and gametocytes are the sexual forms. So the first stage injected is sporozoites.