Alexandria University Student name: Medical Research Institute Semester: Fall Department of Parasitology Academic year: 2019-2020 Doctorate Degree Time allowed: 60 minutes Course title: Adv. Parasitology I Date: ………………. Course code: 1707801 Total marks: 10 marks Midterm Exam ___________________________________________________________________________ Question 1: (6 marks, 0.6 each) I. Choose the correct answer ( each o.5 mark) 1- Egg shell of this Schistosome is not acid fast a- S. Mansoni b- S. Matheei @ c- S. Haematobium d- S. Intercalatum 2- Cercariae of schistosomes in fresh water are influenced by the effect of all of the following except a- Gravity b- Agitation c- Density @ d- Light 3- Life span of schistosomal miracidium of in fresh water is about a- 12 hours @ b- 24 hours c- 48 hours d- 72 hours 4- Growth and pairing of S. haematobium occur in a- Urinary bladder b- Vesical plexus c- Mesenteric veins d- Liver @ 5- The possible mechanisms of immune evasion of schistosomes are all except a- Production of host like antigen b- Changing of tegument c- Production of specific immunoglobulin @ d- Acquiring host antigen 6- Haematemsis in schistosomiasis is due to a- Bilharzial cor pulmonale b- Hepatic dysfunction c- Splenomegaly d- Rupture of oesophageal varices @ 7- Cerebral granulomatous reaction may be caused by egg of a- S. intercalatum b- S. japonicum @ c- S. mansoni d- S. haematobium 8- Consumption of raw fish or shellfish is associated with infection caused by a. Clonorchis sinensis @ b. Ancylostoma duodenale c. Schistosoma japonicum d- Fasciola hepatica 9- Pirenella conica is intermediate host of . a) Heterophyes heterophyes . @ b) fascoila . c) Dicrocoelium dendriticum . d) none of the above 10- Visceral larva migrans :One statement is wrong a. Ingestion of embryonated eggs of A. lumbricoides @ b. Ingestion of embryonated eggs of Ascaris of dogs &cats c. Treatment by hetrazan d. Hyper-esinophilia is common 11- Perianal itching is due to: a. Dead males of E. vermicularis after fertilization b. Female E. vermicularis lay eggs in perianal region @ c. Patients scratching the perianal region to relieve itching d. Invasion of infective larvae to human skin 12- Lofflers syndrome is due to: a. Adult Ascaris worms in the intestine b. Migration of adult worm to ectopic foci c. Inflammatory reaction in the lung due to Ascaris larvae @ d. Synthetization against Ascaris antigens Question no. 2: (4 marks, 2 each) Give short notes : 1- Pathological changes occurring in ascariasis during migratory stage Answer § If the number of the larvae are small , no pathological changes are note. § when the intensity of infection is high,the pathological changes are : § Eosinophilic infiltration & granulomatous reaction around the path of the migrating larvae in the lung &liver . Later on fibrosis occur in the lung . § This process is known as ascaris pneumonitis . § In peripheral blood there is eosinophilia ( Loffler's syndrome ),eosinophilis is usually peaks during the period of migration & decline after the worm re-enter the gut 2- General characters of Cestodes Answer: • Flat, ribbon shaped and segmented, hence called tape worms. • 2- Covered by cuticle. • 3- No body cavity, various systems are embedded in parenchymatous tissue. • 4- No digestive system. They feed by diffusion through the cuticle. Any cestode is formed of scolex (head), neck and strobila (chain of segments). • Excretory and nervous systems are present. • Genital system: hermaphrodite; each mature segment contains male and female genital systems. Common genital pores are either ventral or lateral. .