MIP-260 Exam #2 questions with verified solutions 2023/2024

MIP-260 Exam #2Apicomplexans' transmission - correct answer Have cyst/spore-like structures - in some, cyst wall is absent and development of infective stages in completed in invertebrate vector Structure and function of apical complex - correct answer Polar rings: usually one or two present Conoid: truncated cone of spirally arranged fibrillary structures within polar rings Subpellicular microtubules: radiate from polar rings and run posteriorly Micronemes: smaller, convoluted elongated bodies that extend posteriorly from the complex Rhoptries: extend to cell membrane within polar rings (participate in adhesion/penetration of host cell) Apicomplexa characteristics - correct answer All are parasitic (no cilia or flagella); Reproduction (asexual and sexual) Hepatozoans (Family of Apicomplexa) - correct answer - Blood feeding arthropods are definitive hosts - Transmission usually by consumption of DH rather than by bite Hepatozoan americanum - correct answer - Meronts occur in muscle - Gamonts occur in leukocytes (penetrate gut, develop into gametes and fuse to form oocysts; in adults, sporocysts develop within oocysts and dog becomes infected after eating a tick) - Ticks are definitive hosts - Nymphal ticks become infected when feeding on dogs Hepatozoan americanum: clinical signs - correct answer Elevated temp., weight loss, anemia, lethargy, decreased mobility in hind limbs Eimeriidae general characteristics (Family of Apicomplexa) - correct answer - Microphyle: tiny opening; may be covered by micropylar cap - Refractile polar granule: lies within oocyst - Oocyst wall and sporocyst wall are resistant to harsh conditions Eimeriidae reproduction - correct answer - Gametogony: sexual process where gametes are formed (usually occur in host) - Sporogony: asexual process of spore production (usually occur outside host) - Merogony/Schizogony: asexual reproduction by multiple fission (usually occur in host) Eimeriidae: host and site specificity - correct answer - Species specific - Given species may be limited to a certain organ system, specific regions in that system, cells in a zone, etc. - Many coccidia found in the GI tract (some found in liver, kidneys, other organs) Eimeriidae infections - correct answer - Eimeria spp. vary in pathogenicity - Ind. hosts may not exhibit illness - Some species highly pathogenic, with every GI cell infected - Some species infections are self-limiting (hosts may develop partial immunity to reinfection) Eimeria tenella - correct answer