MLT GlobeMOH exam preparation (UAE) – page 11
700 practice MCQs for the MOH medical laboratory exam. Level: Basic to intermediate.
Which statement about human malaria is INCORRECT?
Gametocytes develop inside red blood cells in the circulation, not in the gut. The other statements correctly describe the cycle.
Which species of the genus Entamoeba causes invasive disease (dysentery, liver abscess) in humans?
E. histolytica is the pathogenic species. E. coli, E. hartmanni and the morphologically identical E. dispar are non-invasive commensals.
Which tapeworm lives as an adult in the intestine of dogs, the 'dog tapeworm' that causes hydatid cysts in humans?
Dogs are the definitive hosts of E. granulosus; humans and sheep acquire hydatid cysts by ingesting eggs from dog faeces.
Which disease is transmitted by the bite of infected Phlebotomus sandflies?
Phlebotomus (Old World) and Lutzomyia (New World) sandflies transmit Leishmania. Dengue and yellow fever are Aedes-borne; malaria is Anopheles-borne.
Ultrasound shows a liver cyst with daughter cysts in a shepherd; aspirated fluid contains protoscolices ('hydatid sand'). Which parasite?
Hydatid cysts with daughter cysts and protoscolices are the larval stage of E. granulosus, acquired from dog faeces.
The chills and fever of a malaria paroxysm coincide with which event in the parasite's cycle?
When schizonts rupture, merozoites and pyrogenic parasite material are released, triggering cytokine-driven fever. Liver-stage events are clinically silent.
Adult Wuchereria bancrofti worms reside in the:
Adults live in lymphatics and release microfilariae into the blood. Subcutaneous tissue and eye are sites for Onchocerca and Loa loa.
Leishmania donovani amastigotes are found in all of these except:
L. donovani is an intracellular parasite of mononuclear phagocytes, including Kupffer cells and splenic macrophages. It does not infect erythrocytes, unlike Plasmodium or Babesia.
Which parasite can be seen as motile flagellates in a wet mount of vaginal or urethral discharge?
Jerky motile pear-shaped trophozoites with an undulating membrane in saline mounts are diagnostic of T. vaginalis. The others are intestinal parasites found in stool.
Humans acquire Ascaris lumbricoides by swallowing:
Eggs become infective after about 2 to 3 weeks in soil when a larva develops inside. Filariform skin penetration is typical of hookworm and Strongyloides.
River blindness is another name for:
Onchocerca volvulus, spread by Simulium blackflies breeding near rivers, damages the eye. Loiasis is eye worm disease without blindness.
Which intestinal protozoan can spread to cause liver and brain abscesses?
Invasive E. histolytica can reach the liver through the portal vein and occasionally the brain or lungs. Balantidium rarely spreads beyond the colon.
The sheep liver fluke that can infect humans who eat raw watercress is:
Metacercariae of F. hepatica encyst on water plants like watercress; adults live in bile ducts. Clonorchis comes from raw fish and Fasciolopsis is an intestinal fluke.
Which sugar gives a negative copper-reduction (Benedict) test in urine?
Sucrose has no free anomeric carbon, so it is non-reducing. Fructose, galactose and arabinose are reducing sugars and give a positive result.
The main sugar in seminal fluid that supplies energy for sperm motility is:
Fructose is secreted by the seminal vesicles; low levels suggest seminal vesicle obstruction or absence. Glucose is not the main seminal sugar.
Which test best assesses intestinal fat absorption?
Quantitative 72-hour fecal fat measures steatorrhea caused by malabsorption or pancreatic insufficiency. Amylase and lipase mainly reflect acute pancreatitis.
An arthropod with three pairs of legs and a body in three parts belongs to class:
Insects (lice, fleas, mosquitoes) have head, thorax, abdomen and six legs. Adult arachnids such as ticks and mites have four pairs.
Which helminth infects the largest number of people worldwide?
Ascaris is the most common soil-transmitted helminth, infecting several hundred million people. Trichinella and Strongyloides are far less common.
Elephantiasis of the legs or scrotum is most often caused by:
W. bancrofti (and Brugia species) cause lymphatic filariasis, leading to chronic lymphedema. The others are intestinal or hepatic helminths.
Which property does NOT belong to IgM?
IgE, not IgM, sensitizes mast cells in allergy. IgM is the first antibody made, is a strong complement activator, and monomeric IgM is a B-cell receptor.