Chpt 6a Insects Of Medical Importance Flashcards
- Which of these is NOT a characteristic of insects? a) They belong to the phylum Arthropoda. b) They are bilaterally symmetrical. c) They have an open circulatory system with haemolymph. d) They have four pairs of wings.
Answer: d) They have four pairs of wings. Explanation: Insects have three pairs of legs and generally one or two pairs of wings.
- Which of the following insects is responsible for the transmission of trypanosomiasis? a) Butterflies b) Tsetse flies c) Bees d) Moths
Answer: b) Tsetse flies Explanation: Tsetse flies are vectors of trypanosomiasis also known as sleeping sickness.
- Which of these is a characteristic of chewing lice? a) They have sucking mouth parts. b) They feed on feathers or hair. c) They are major vectors of human diseases. d) They have piercing and sucking mouth parts.
Answer: b) They feed on feathers or hair. Explanation: Chewing lice feed on feathers or hair and are sometimes referred to as chewing lice.
- Pediculus humanus is commonly known as: a) Chewing louse b) Head louse c) Pubic louse d) Body louse
Answer: b) Head louse Explanation: Pediculus humanus is the scientific name for the human head louse.
- How long does the egg stage of the head louse typically last? a) 1-2 days b) 3-4 days c) 6-9 days d) 10-12 days
Answer: c) 6-9 days Explanation: The text states that eggs hatch in 6-9 days depending on temperature.
- Which disease is caused by Rickettsia prowazekii and transmitted by lice? a) Relapsing fever b) Typhus c) Trench fever d) Scabies
Answer: b) Typhus Explanation: The text states that typhus is caused by a rickettsial organism Rickettsia prowazekii.
- Which of these is a symptom of pediculosis? a) High fever b) Severe itching c) Hair loss d) Skin discoloration
Answer: b) Severe itching Explanation: Pediculosis an infestation with lice results in irritability lousy feeling dermatitis or severe itching.
- Where on the human body is Pthirus pubis typically found? a) Head b) Pubic region c) Armpits d) Feet
Answer: b) Pubic region Explanation: The pubic louse (Pthirus pubis) is typically found in the hairs of the pubic region.
- Which of these is NOT a control measure for pubic lice? a) Shaving of pubic hair b) Use of insecticides c) Washing hair with hot water d) Taking antibiotics
Answer: d) Taking antibiotics Explanation: Antibiotics are not effective against lice. Control methods include shaving pubic hair using insecticides and washing hair with hot water.
- What type of mouth parts do bed bugs possess? a) Chewing b) Piercing and sucking c) Siphoning d) Sponging
Answer: b) Piercing and suckingExplanation: The text states that Hemipterans have sucking mouthparts. Bed bugs belong to the order Hemiptera.
- Which of the following diseases is NOT transmitted by fleas? a) Plague b) Typhus c) Tapeworm d) Malaria
Answer: d) Malaria Explanation: Malaria is transmitted by mosquitoes not fleas.
- Which bacteria is responsible for causing plague? a) Rickettsia typhi b) Yersinia pestis c) Bartonella quintana d) Borrelia recurrentis
Answer: b) Yersinia pestis Explanation: The text states that plague is transmitted by Xenopsylla cheopis and Pulex irritans. Both of these fleas pick up the bacterium Yersinia pestis during a blood meal.
- Which flea species is the primary vector for the transmission of plague? a) Ctenocephalides canis b) Ctenocephalides felis c) Pulex irritans d) Xenopsylla cheopis
Answer: d) Xenopsylla cheopis Explanation: The text states that plague which is primarily a zoonosis is transmitted mainly by Xenopsylla cheopis.
- What is the major intermediate host for flea-borne typhus? a) Pulex irritans b) Ctenocephalides canis c) Xenopsylla cheopis d) Tunga penetrans
Answer: c) Xenopsylla cheopis Explanation: The major intermediate host for flea-borne typhus is Xenopsylla cheopis but other fleas can also be involved.
- Where do sand-flies typically lay their eggs? a) On the surface of water b) In the fur of animals c) In crevices burrows tree holes d) On plants
Answer: c) In crevices burrows tree holes Explanation: Females lay eggs in crevices burrows tree holes and other places with high humidity and debris.
- What type of mouth parts do sand-flies possess? a) Piercing and sucking b) Chewing c) Sponging d) Siphoning
Answer: a) Piercing and sucking Explanation: Sand-flies have sucking mouthparts. They have brownish hairy mouthparts.
- Which of these diseases is NOT transmitted by sand-flies? a) Sand fly fever b) Leishmaniasis c) Bartonellosis d) Plague
Answer: d) PlagueExplanation: Plague is transmitted by fleas not sandflies.
- What is the causative agent of leishmaniasis? a) A bacteria b) A virus c) A protozoan d) A helminth
Answer: c) A protozoan Explanation: Leishmaniasis is a protozoan disease caused by a flagellate Leishmania.
- Which form of Leishmania is found in the sandfly? a) Amastigote b) Promastigote c) Epimastigote d) Trypomastigote
Answer: b) Promastigote Explanation: The sandfly bite injects promastigotes into a new host.
- Which of these is a symptom of visceral leishmaniasis? a) Skin lesions b) Enlarged spleen c) Hair loss d) Fever and chills
Answer: b) Enlarged spleen Explanation: Visceral leishmaniasis affects the internal organs e.g. liver spleen and bone marrow.
- Where in the human body does the Onchocerca volvulus reside? a) Blood vessels b) Lymphatic system c) Intestines d) Subcutaneous tissues
Answer: d) Subcutaneous tissues Explanation: Adult female O. volvulus are found in subcutaneous tissues of man either free or in nodules.
- How long does it take for Onchocerca volvulus to reach adult stage? a) 1-2 months b) 3-6 months c) 6-12 months d) 12-18 months
Answer: d) 12-18 monthsExplanation: The period from infection to production of microfilariae by the female is between 12 months to reach adult stage.
- Which of these is a symptom of onchocerciasis? a) Fever b) Blindness c) Paralysis d) Swelling of the liver
Answer: b) Blindness Explanation: Onchocerciasis is also known as river blindness.
- What are the tiny air tubes that make up the respiratory system in insects called? a) Spiracles b) Tracheae c) Malpighian tubules d) Haemolymph
Answer: b) Tracheae Explanation: Insects breathe using a tracheal system composed basically of a dorsally placed heart which pumps blood posteriorly by means of an open tracheal system with openings to the outside known as spiracles.
- Which of these insect orders is characterized by having two wings? a) Coleoptera b) Diptera c) Hymenoptera d) Lepidoptera Answer: b) Diptera
Explanation: Diptera which means ‘two wings’ includes insects like mosquitos and flies.
- What is the term for the hard protective outer covering found in insects? a) Exoskeleton b) Endoskeleton c) Cuticle d) Carapace
Answer: a) Exoskeleton Explanation: Insects have a hard exoskeleton composed of chitin.
- Which insect order is known for its social behavior and includes ants and bees? a) Isoptera b) Hymenoptera c) Orthoptera d) Hemiptera
Answer: b) Hymenoptera Explanation: Hymenoptera include bees wasps and ants.
- What is the name of the fluid that circulates in an insect’s open circulatory system? a) Blood b) Lymph c) Haemolymph d) Plasma
Answer: c) HaemolymphExplanation: Insects have an open circulatory system containing haemolymph.
. Which of these insects is known for its ability to jump long distances? a) Grasshopper b) Butterfly c) Flea d) Beetle
Answer: c) Flea Explanation: Fleas are well-known for their jumping ability. They have powerful legs with enlarged coxae for jumping.
- Which insect order is known for having scales on their wings? a) Lepidoptera b) Coleoptera c) Diptera d) Hemiptera
Answer: a) Lepidoptera Explanation: Lepidoptera include butterflies and moths which are known for their scaled wings.
- What is the name of the specialized mouthparts found in butterflies and moths used for feeding on nectar?
Answer: Proboscis.
- What is the term for the developmental stage in some insects where they undergo a complete transformation including a pupal stage?
Answer: Complete metamorphosis.
- Name one disease transmitted by the tsetse fly.
Answer: Trypanosomiasis (African sleeping sickness).
- What is the term for the condition of being infested with lice?
*Answer**: Pediculosis.
- What type of mouthparts do sucking lice possess?
Answer: Piercing and sucking mouthparts.
- Name the bacterial disease transmitted by body lice.
Answer: Trench fever (Bartonella quintana).
- What is the common name for insects in the order Hemiptera?
Answer: True bugs.
- What is the term for the shedding of the exoskeleton in insects?
Answer: Molting or ecdysis.
- Name one disease transmitted by fleas.
Answer: Plague.
- What is the name of the protozoan parasite that causes malaria?
Answer: Plasmodium.
- What is the name of the specialized mouthparts found in butterflies and moths used for feeding on nectar?
Answer: Proboscis.
- What is the term for the developmental stage in some insects where they undergo a complete transformation including a pupal stage?
Answer: Complete metamorphosis.
- Name one disease transmitted by the tsetse fly.
Answer: Trypanosomiasis (African sleeping sickness).
- What is the term for the condition of being infested with lice?
*Answer**: Pediculosis.
- What type of mouthparts do sucking lice possess?
Answer: Piercing and sucking mouthparts.
- Name the bacterial disease transmitted by body lice.
Answer: Trench fever (Bartonella quintana).
- What is the common name for insects in the order Hemiptera?
Answer: True bugs.
- What is the term for the shedding of the exoskeleton in insects?
Answer: Molting or ecdysis.
- Name one disease transmitted by fleas.
Answer: Plague.
- What is the name of the protozoan parasite that causes malaria?
Answer: Plasmodium.
- How long does it typically take for bed bug eggs to develop into mature adults? a) 1-2 weeks b) 1-4 months c) 3-4 months d) 1 year
Answer: b) 1-4 months Explanation: The development of eggs to mature adults in bed bugs takes 1-4 months.
- Which disease is transmitted by Triatoma bugs? a) Malaria b) Yellow Fever c) Chagas disease d) Trypanosomiasis
Answer: c) Chagas diseaseExplanation: Triatoma bugs also known as kissing bugs are known for transmitting Chagas disease.
- What is the typical size range of Triatoma bugs? a) 5-10mm b) 10-15mm c) 15-20mm d) 20-30mm
Answer: d) 20-30mm Explanation: The text describes Triatoma bugs as relatively large ranging from 20-30 mm in length.
- What happens to the trypomastigotes ingested by the Triatoma bug? a) They are destroyed in the gut. b) They multiply and develop in the gut. c) They are transmitted directly to humans. d) They are encapsulated and remain dormant.
Answer: b) They multiply and develop in the gut. Explanation: When the bug feeds it picks up trypomastigotes which multiply and develop in the gut of the bug into epimastigotes.
- Which of these is NOT a control measure for Triatoma bugs? a) Use of residual insecticides b) Use of mosquito nets c) Removing and repairing walls d) Plastering and preserving walls
Answer: b) Use of mosquito nets Explanation: Mosquito nets are not effective against Triatoma bugs.
- What is the feeding habit of fleas? a) They feed on plant sap b) They feed on blood c) They feed on decaying matter d) They feed on other insects
Answer: b) They feed on blood Explanation: Fleas are parasites that feed on the blood of their hosts.
- Where do female fleas typically lay their eggs? a) In cracks and crevices of walls b) On the ground in the host’s dwelling place c) On the host’s body d) In water sources
Answer: b) On the ground in the host’s dwelling place Explanation: Female fleas lay eggs in batches in accumulated debris dust or dirt on floors in the host’s dwelling place.
- Which stage of the flea life cycle is responsible for disease transmission? a) Egg b) Larva c) Pupa d) Adult
Answer: d) Adult Explanation: Adult fleas are responsible for biting and transmitting diseases.
- What is the common name for Tunga penetrans? a) Human flea b) Rat flea c) Chigoe flea d) Cat flea
Answer: c) Chigoe flea Explanation: Tunga penetrans is medically called the chigoe jigger chigger chique or sand flea.
- Where on the human body does the female Tunga penetrans typically burrow? a) Scalp b) Armpits
- Which species of Leishmania is the causative agent of kala-azar? a) L. tropica b) L. braziliensis c) L. major d) L. donovani
Answer: d) L. donovaniExplanation: Kala-azar is caused by L. donovani.
- What is the treatment for leishmaniasis? a) Antibiotics b) Antivirals c) Antiparasitics d) Antifungals
Answer: c) Antiparasitics Explanation: Leishmaniasis is caused by a protozoan parasite. Treatment is with antiparasitic drugs such as sodium stibogluconate amphotericin B pentamidine and miltefosine.
- Which of these is NOT a control measure for leishmaniasis? a) Mass treatment b) Control of sand flies c) Vaccination d) Personal protection
Answer: c) Vaccination Explanation: There is no vaccine for leishmaniasis.
- To which order do mosquitoes belong? a) Hemiptera b) Diptera c) Siphonaptera d) Anoplura
Answer: b) Diptera Explanation: Mosquitoes belong to the order Diptera.
- Which of these mosquito species is NOT a known vector of diseases? a) Anopheles b) Culex c) Aedes d) Mansonia
Answer: None of the Above Explanation: All four mosquito species are known vectors of diseases: Anopheles for malaria Culex for filariasis and Japanese encephalitis Aedes for yellow fever and dengue fever and Mansonia for Brugian filariasis.
- What is the characteristic shape of Anopheles mosquito eggs? a) Round and smooth b) Elongated and pointed c) Boat-shaped and have floats d) Curved and have spines
Answer: c) Boat-shaped and have floats Explanation: Anopheles eggs are boat-shaped and have floats while Culex eggs are laid singly or in masses and never contain floats.
- How long does the larval stage of a mosquito typically last? a) 1-2 days b) 3-4 days c) 7-10 days d) 14-21 days
Answer: c) 7-10 days Explanation: The larval stage lasts for about 7-10 days depending on species.
- Which of these is NOT a medical importance of mosquitoes? a) Biting nuisance b) Vectors of diseases c) Source of food for other animals d) Pollination of plants
Answer: d) Pollination of plants Explanation: Mosquitoes are not known to pollinate plants.
- What is the causative agent of malaria? a) A virus b) A bacteria c) A protozoan d) A helminth
Answer: c) A protozoan Explanation: Malaria is caused by protozoan parasites of the genus Plasmodium.
- Which stage of the Plasmodium life cycle infects mosquitoes? a) Sporozoite b) Merozoite c) Gametocyte d) Ookinete
Answer: c) GametocyteExplanation: Mosquitoes bite an infected person and pick up gametocytes which further develop in the mosquito.
- What causes the obstruction of lymphatics in lymphatic filariasis? a) Accumulation of fluid b) Presence of adult worms c) Inflammation d) Formation of nodules
Answer: c) Inflammation Explanation: Lymphatic filariasis causes obstruction of the lymphatics by inflammation.
- What are the two basic forms of Brugia malayi and Brugia timori in bancroftian filariasis? a) Nocturnal and diurnal b) Periodic and subperiodic c) Acute and chronic d) Symptomatic and asymptomatic
Answer: b) Periodic and subperiodic Explanation: Brugia malayi and Brugia timori both exist in two basic forms–nocturnal periodic form in which microfilariae are in peripheral blood only at night. In subperiodic forms microfilariae occur in peripheral blood both during the day and night though a slight periodicity still exists.
- Which of these viruses causes yellow fever? a) Dengue virus b) Zika virus c) Chikungunya virus d) Yellow fever virus
Answer: d) Yellow fever virus Explanation: Yellow fever is a viral disease.
- What is the typical incubation period for yellow fever? a) 1-2 days b) 2-3 days c) 3-6 days d) 7-10 days
Answer: c) 3-6 days Explanation: The incubation period of yellow fever infection is typically epidemic in character. The incubation period of the virus is 3-6 days and on recovery an individual tends to acquire long-lasting immunity.
- Which of these mosquito species is the primary vector of dengue fever? a) Aedes aegypti b) Anopheles gambiae c) Culex quinquefasciatus d) Mansonia uniformis
Answer: a) Aedes aegypti Explanation: Dengue haemorrhagic fever is transmitted by Aedes aegypti and other container-breeding mosquitoes.
- Which of these is a characteristic of Simulium adults? a) They have long legs and a slender body. b) They are brightly coloured. c) They are strong fliers. d) They have piercing and sucking mouthparts.
Answer: c) They are strong fliers. Explanation: Blackflies are powerful fliers and can cover long distances.
- What do Simulium larvae feed on? a) Blood b) Plant juices c) Algae and diatoms d) Other insects
Answer: c) Algae and diatoms Explanation: Simulium larvae primarily feed on algae and diatoms.
- Where do female Simulium lay their eggs? a) In stagnant water b) On vegetation near water c) In fast-flowing water d) On the bodies of animals
Answer: c) In fast-flowing water Explanation: Blackflies breed in fast-flowing waters of streams and rivers with high oxygen content.
- Which of these is NOT a medical importance of black flies? a) Annoyance b) Blood loss c) Allergic reactions d) Transmission of malaria
Answer: d) Transmission of malaria Explanation: Black flies do not transmit malaria. Malaria is transmitted by mosquitos.
- What is the causative agent of onchocerciasis? a) A virus b) A bacteria c) A protozoa d) A filarial nematode
Answer: d) A filarial nematode Explanation: Human onchocerciasis commonly called river blindness is a chronic disease caused by the filarial nematode Onchocerca volvulus.
