Biology · General Awareness

Disease Vectors and Pathogens

820 Questions

Disease vectors and pathogens examine how organisms like Plasmodium and Leishmania transmit infections. Test items require matching vectors to specific diseases. Studying these life cycles is essential for scoring well.

Plasmodium infective stagesDisease transmission modesDisease vectors and fleasIntracellular parasitesElephantiasis causes

Disease Vectors and Pathogens Questions

Multiple choice

Which organ is affected by the malaria?

  1. Stomach

  2. Intestine

  3. Liver

  4. Spleen

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Malaria is a disease caused by Plasmodium parasites that infect red blood cells and the liver. The spleen is significantly affected because it works to filter out the damaged and infected red blood cells, which often leads to its enlargement (splenomegaly). While the liver is also involved, the spleen is a classic clinical indicator of the disease's impact.

Multiple choice

Match the following diseases with their causative agents and vectors.

   
Disease
Causative agent
Vector
P. Kala azar i. Plasmodium spp. 1. Tse-tse fly
Q. African sleeping sickness ii. Leishmania donovani 2. Sand fly
R. Epidemic typhus iii. Trypanosoma brucei 3. Mosquito
S. Malaria iv. Rickettsia prowazekii 4. Body louse

  1. P - ii - 3, Q - iv - 1, R - i - 2, S - iii - 4

  2. P - iii - 1, Q - iv - 2, R - ii - 4, S - i - 3

  3. P - i - 2, Q - ii - 4, R - iii - 2, S - iv - 3

  4. P - ii - 2, Q - iii - 1, R - iv - 4, S - i - 3

  5. P - i - 4, Q - iii - 1, R - ii - 3, S - iv - 2
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Kala azar is caused by Leishmania donovani and transmitted by the bite of sand fly. African Trypanosomiasis (also known as sleeping sickness) is caused by Trypanosoma brucei and transmitted by tse-tse fly. Epidemic typhus is caused by Rickettsia prowazekii and transmitted by the human body louse (Pediculus humanus corporis). Malaria is a mosquito-borne infectious disease of humans and other animals caused by parasites of Plasmodium spp.

Multiple choice

Malaria is caused by

  1. bacteria

  2. virus

  3. protozoa

  4. fungus
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Malaria is a disease caused by parasitic protozoa of the genus Plasmodium. It is transmitted to humans through the bite of an infected Anopheles mosquito.

Multiple choice

Which of the following is not a parasite?

  1. Louse

  2. Mosquito

  3. Tick

  4. Housefly
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A parasite lives on or in a host and benefits at the host's expense. Louse, mosquitoes, and ticks are parasites. A housefly is a scavenger or vector, not a biological parasite.

Multiple choice

Chagas disease is an inflammatory, infectious disease caused by a parasite found in the faeces of the triatomine (reduviid) bug. Which of the following trypanosoma species has been proposed for the prevention of Chagas disease?

  1. Trypanosoma rangeli

  2. Trypanosoma suis

  3. Trypanosoma irwini

  4. Trypanosoma brucei

  5. Trypanosoma cruzi
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Trypanosoma rangeli is considered non pathogenic in humans. It has been proposed for the prevention of Chagas disease.

Multiple choice

Which of the following statements does NOT characterise the life cycle of P. falciparum in the female Anopheles mosquito?

  1. The sporozoites complete their differentiation in the salivary glands of mosquito.

  2. Immature sporozoites break through the oocyst wall into the haemolymph.

  3. The ookinete is an invasive form of P. falciparum within the mosquito.

  4. During the ookinete stage, genetic recombination can occur.

  5. The ookinete is the only haploid stage of P. falciparum.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Fertilisation of the female gamete by the male gamete occurs rapidly after gametogenesis.

Multiple choice

The parasitic protozoan capable of developing immediately beneath the brush-border of the intestinal epithelium after infection is

  1. acroeimeriaa

  2. eimeria

  3. hemiptera

  4. anthemosoma

  5. ascetosporea
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Acroeimeria is a genus of protozoan parasite that contains those parasites which initially develop immediately beneath the brush-border of the intestinal epithelium, but the meronts and gamonts of which are early on extruded to form a layer on the surface of the gut mucosa.