Biology · General Awareness

Disease Vectors and Pathogens

844 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 of the following conditions though harmful in itself, is a potential saviour from all mosquito borne infectious disease like malaria?

  1. Pernicious anaemia

  2. Hemolytic anaemia

  3. Leukemia

  4. Thalassemia

  5. Sickle cell anaemia
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Sickle cell anemia is a blood disease in which red blood cells reveal an abnormal crescent (or sickle) shape when observed under a conventional microscope. It provides immunity against malaria.

Multiple choice

Match the following:

Causative agent Disease
a. Staphylococci 1. Sleeping sickness
b. Trypanosoma 2. Kala-azar
c. Leishmania 3. Acne

  1. a - 1, b - 2, c - 3

  2. a - 2, b - 1, c - 3

  3. a - 2, b - 3, c - 1

  4. a - 3, b - 2, c - 1

  5. a - 3, b - 1, c - 2
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

The correct matching is given below. Staphylococci : the bacteria that can cause acne Trypanosoma : the protozoan that causes sleeping sickness Leishmania : the protozoan that causes kala-azar

Multiple choice

Treponema pallidum is a

  1. prokaryotic commensal

  2. eukaryotic parasite

  3. spirochete

  4. protozoan parasite

  5. mycoplasma
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Treponema pallidum is a spirochete because it is spiral shaped and moves with the help of axial filaments or endo-flagella. It is a prokaryote and a pathogenic spirochete - the causative agent of syphilis in human beings.

Multiple choice

Which of the following organisms causes malignant malaria?

  1. Plasmodium malariae

  2. Plasmodium vivax

  3. Plasmodium ovale

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

Plasmodium falciparum causes malignant tertian malaria (falciparum malaria), the most severe and life-threatening form. P. vivax causes vivax malaria (benign tertian), P. malariae causes quartan malaria, and P. ovale causes ovale malaria (mild tertian). Only P. falciparum is termed 'malignant' malaria.

Multiple choice

IgE levels are high in infections with

  1. Trichinella spiralis

  2. Trypanosoma cruzi

  3. Trypanosoma rhodesiense

  4. Plasmodium falciparum

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

Parasites like Trichinella frequently increase the IgE levels, usually polyclonally. This tends to inhibit the protective effect of IgE by diluting out the specific IgE on the mast cell. Inflammation induced by mast cell degranulation leads to influx of IgG, which causes damage to the parasite.

Multiple choice

Other than spreading malaria, anopheles mosquitoes are also vectors of

  1. encephalitis

  2. dengue fever

  3. yellow fever

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

It is a serious concern that malaria can go on to spread far and wide because when an anopheles is contaminated with malaria, it stays within it for life and this infects all those that it bites. It is found that the malaria infected anopheles mosquito has more appetite than an uninfected mosquito. This makes the potential spread of malaria. Other than spreading malaria, anopheles mosquitoes are also vectors of filariasis, which is a disease caused by nematodes in the blood or tissues of the body causing blockage of lymphatic vessels.

Multiple choice

__________ are facultative parasites.

  1. Pinnotheresostreum and Muicobacterium tuberculosis

  2. Entamoeba hystolytica and Ascaris lumbicoids

  3. Fasciola hepatica and Pinnotheres ostreum

  4. Ascaris lumbicoids and Muicobacterium tuberculosis

  5. Fasciola hepatica and Entamoeba hystolytica
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Organisms which may be parasitic or free living at will, i.e., can live as free living forms in absence of a host are called facultative parasites. Examples: Pinnotheres ostreum and Muicobacterium tuberculosis

Multiple choice

Which of the following matches of ‘Disease – causative agent – vector’ is correct?

  1. African sleeping sickness – Trypanosoma cruzi – Tse-tse fly

  2. Kala Azar – Leishmania donovani – Sand fly

  3. Malaria – Plasmodium sp. – female Culex mosquito

  4. Filariasis – Wuchreria bancrofti – female Anopheles mosquito

  5. Chaga’s disease – Trypanosoma gambiense – Tse-tse fly
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Kala Azar is caused by Leishmania donovani. Vector: Sand fly

Multiple choice

Match the following: Names of parasitic nematodes|Diseases| |a. Ascaris|1. Elephantiasis| |b. Wuchereria bancrofti|2. Ascariasis| |c. Enterobius|3. Enterobiasis|

  1. a - 2, b - 1, c - 3

  2. a - 2, b - 3, c - 1

  3. a - 3, b - 2, c - 1

  4. a - 1, b - 2, c - 3

  5. a - 3, b - 1, c - 2
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 Parasitic nematode Ascaris causes ascariasis disease. Parasitic nematode Wuchereria bancrofti causes elephantiasis. Parasitic nematode Enterobius causes enterobiasis.

Multiple choice

Which of the following are correct regarding Entamoeba histolytica? P. Digenetic life cycle Q. Trophozoite is adult and harmful stage R. Causes amoebic dysentery in humans S. Reserve food material is starch Select the correct option using codes given below:

  1. P and Q

  2. P and R

  3. P and S

  4. Q and R

  5. R and S
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The adult and harmful stage of Entamoeba histolytica is called trophozoite. Entamoeba histolytica causes amoebic dysentery in humans.

Multiple choice

Elephantiasis is a parasitic infection that causes extreme swelling in the arms and legs. It is caused by animals which belong to the phylum

  1. Platyhelminthes

  2. Coelentrates

  3. Annelids

  4. Nematodes

  5. NA
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

It is the correct answer as Elephantiasis is caused by filarial worms, which belong to phylum Nematodes. They are parasitic worms having tissue level of organisation. They are triploblastic animals having bilateral symmetry.

Multiple choice

Directions: The following question consists of certain statements. You have to select the option representing the most logical sequencing of the given statements.

A. Malaria is caused by a protozoan bacteria. B. Anopheles mosquitoes are the carriers of this protozoan bacteria. C. Malaria results from mosquito bites. D. Mosquitoes cause malaria if they are bitten. E. Mosquitoes do not cause malaria. F. All mosquitoes do not cause malaria.

  1. ACD

  2. ABF

  3. BDE

  4. AEF
Reveal answer Fill a bubble to check yourself
B Correct answer