First One Hour Exam

ENT 561 Exam 1, p.1

ENT 561

First One Hour Exam

September 29, 2009

Name: ______

Section A Picture Questions 10 points each.

1. (a) The common name of this insect is: ______

(b) It is a member of the insect order: ______

___ House Flies___ Mosquitoes

___ Crane Flies___ Drain Flies

___ Plane Flies___ Maine Flies

2. (a) Answer only one of the following two options: This thing is a/an:

Insect because it has/lacks ______

______

Non-insect arthropod because it has/lacks: ______

______

(b) It transmits pathogens responsible for (check all that apply):

___ Epidemic Typhus___ Scrub Typhus

___ Relapsing Fever___ Hay Fever

___ Leishmaniasis___ Trench Fever

___ Chagas’ Disease___ Trypanosomyiasis

3. In this generalized insect-vertebrate interaction, possible pathogen locations/transmission ways are numbered 1 – 8. Ignore the lower case letters in this diagram. Use the numbers to answer the following questions:

___ (a) Where does the plague bacterium replicate?

___ (b) Which pathway does Trypanosoma cruzi use to escape from the insect?

___ (c) What tissue is initially invaded by the etiological agent of epidemic typhus?

___ (d) What pathway does Yersinia pestis use to escape from the insect?

(e) VERY BRIEFLY, in terms of this picture, how is epidemic typhus transmitted?

4. This map shows the distribution of mortality during the Horse Plague.

___ (a) This plague occurred during the time period of: (a) 540 – 550 AD; (b) 1340 – 1350 AD; (c) 1510 – 1520 AD; (d) 1660 – 1670 AD; (e) 1870 -1880 AD

(b) VERY BRIEFLY: Why is the mortality greatest along the coastal areas?

______

(c) The Horse Plague was one of several great plagues to hit Europe and Western Civilization and all of the big ones had names. What is the name of any other one of these great plagues?

______

Section B – Multiple Choice. 3 points each.

___ 1. An epidemic which occurs over a wide geographic area is called a: (a) Epidemic; (b) Pandemic; (c) Endemic; (d) Geodemic; (e) Megademic.

___ 2. A “Predilection Host” is defined as a host which (a) is not necessary to complete the life cycle of the parasite; (b) cannot support parasite transmission; (c) accidentally harbors an organism that is not ordinarily parasitic in the particular species; (d) is used until the appropriate definitive host is reached; (e) None of these.

___ 3. In epidemiology, the term “Periodic Trend” refers to: (a) the occurrence of disease over years; (b) a temporary change in a secular trend; (c) occurrence of disease; (d) seasonal changes in disease occurrence; (e) episodic outbreaks of disease.

___ 4. Which ONE of the following would NOT be a good kissing bug control option: (a) bed nets; (b) replacing mattresses; (c) improved public education; (d) plastering walls; (e) all of these would be GOOD control options.

___ 5. The cockroach considered to be the most important species in the developed world is the: (a) oriental cockroach; (b) brown banded cockroach; (c) German cockroach; (d) American cockroach; (e) brown cockroach.

___ 6. You would find a genal ctenidium on a: (a) flea; (b) cockroach; (c) louse; (d) bed bug; (e) Triatomine

___ 7. The biovar ‘Orientalis’ that we discussed in class, is a strain of: (a) cockroach; (b) flea; (c) bacterium; (d) rickettsia; (e) None of these.

___ 8. An example of a member of the Brachycera is the: (a) louse; (b) house fly; (c) mosquito; (d) sand fly; (e) moth fly.

___ 9. Some beetles can be intermediate hosts of parasites which can infest animals when the beetle is eaten. An example of one of these parasites is: (a) Ctellonoma; (b) horse bots; (c) vampire worms; (d) tapeworms; (e) Pediculus species.

___ 10. Carlos Chagas was a (a) physician from Brazil; (b) medical student from Colombia; (c) medical student from Peru; (d) dermatologist from Mexico; (e) US Army scientist stationed in Cuba.

___ 11. Brill-Zinser disease is associated with (a) plague; (b) Leishmaniasis; (c) American Trypanosomiasis; (d) epidemic typhus; (e) none of these.

___ 12. Stick Tight fleas are easily distinguished from other common fleas of North America by the shape of their (a) head; (b) legs; (c) abdomen; (d) dorso-ventral flattening; (e) lateral flattening.

___ 13. Toxic beetles sometimes ingested by livestock as they consume animal forage in our area are mostly in the family (a) Coccinellidae (b) Scarabaeidae; (c) Cleridae; (d) Meloidae; (e) Histeridae.

___ 14. The gonotrophic cycle of an arthropod refers to its (a) overwintering method; (b) reproductive cycle; (c) migratory mechanism; (d) phenopause; (e) hormonal cycle.

___ 15. In “transstadial transmission,” an insect acquires a pathogen and passes it on to (a) another insect of the same age class; (b) an insect in a different species; (c) a member of the opposite sex; (d) a subsequent life stage of the same insect; (e) a previous live stage of the same insect.

Section C – Short Answer. 5 points each.

1. What is the difference between a Definitive Host and an Intermediate Host?

2. In human-insect-pathogen interactions, humans suffer two general types of damage: Direct and Indirect. Give one example of each that we have discussed in class:

Direct: ______

Indirect: ______

3. VERY BREIFLY: Describe the role of the “epimastigotes” in the life cycle of the etiological agent of American Trypanosomiasis.

4. Briefly describe the difference between a solenophage and a telmophage.

5. Briefly, what is the difference between horizontal transmission and vertical transmission of pathogens?