Tag: evs - i

Questions Related to evs - i

Vectors are

  1. Physalia, Musca domestica and Anopheles

  2. Amoeba Physalia and Musca

  3. Anopheles, Musca and Culex

  4. All the above.


Correct Option: C
Explanation:
  • A disease vector is an agent who carries and transmits an infectious pathogen into another living organism.
  • Female Anopheles mosquito serves as vector for malaria.
  • Musa(house fly)serves as a vector for at least 65 diseases to humans, including typhoid fever, dysentery, cholera, poliomyelitis, yaws, anthrax, tularemia, leprosy, and tuberculosis.
  • Culex mosquito serves as a vector for arbovirus infections such as West Nile virus, Japanese encephalitis, or St. Louis encephalitis, but also filariasis.
  • Hence Vectors are Anopheles, Musca, and Culex.
  • So, the correct answer is 'Anopheles, Musca, and Culex'.

Droplet infection is a mode of 

  1. Direct transmission

  2. Indirect transmission

  3. Pathogen spread through mosquitoes

  4. Fomite transmission


Correct Option: A
Explanation:

Droplet infection is an infection transmitted from one individual to another by droplets of moisture expelled from the upper respiratory tract through sneezing or coughing. Direct transmission occurs when there is physical contact between an infected person and a susceptible person. Droplet infection is a mode of direct transmission in which the infection is transmitted by coughing, sneezing.

So, the correct answer is 'Direct transmission'.

Out of pneumonia, gangrene, yellow fever, dengue fever, malaria and elephantiasis, mosquitoes transmit diseases

  1. 6

  2. 4

  3. 3

  4. 2.


Correct Option: B
Explanation:
  • Diseases transmitted by mosquitoes include: malaria, dengue,Yellow fever,Elephantiasis West Nile virus, chikungunya, filariasis, tularemia, dirofilariasis, Japanese encephalitis, Saint Louis encephalitis, Western equine encephalitis, Eastern equine encephalitis, Venezuelan equine encephalitis, Ross River fever, Barmah Forest fever, La Crosse encephalitis, and Zika fever,as well as newly detected Keystone virus and Rift Valley fever.
  • Out of pneumonia, gangrene, yellow fever, dengue fever, malaria and elephantiasis, mosquitoes transmit 4 diseases they are Yellow fever, dengue, malaria, and elephantiasis.
  • So, the correct answer is '4'.

Vector insects are which

  1. Spread disease

  2. Destroy crop

  3. Spoil soil

  4. Act as scavengers.


Correct Option: A
Explanation:
  • A disease vector is an agent who carries and transmits an infectious pathogen into another living organism.
  • Vector-borne diseases are human illnesses caused by parasites, viruses, and bacteria that are spread by insects like mosquitoes, sandflies, triatomine bugs, black flies, ticks, tsetse flies, mites, snails and lice. For example, Female Anopheles mosquito is a vector for malaria.
  • Hence Vector insects are which spread disease.
  • So, the correct answer is 'Spread disease'.

A disease spread indirectly through a vector is 

  1. Sleeping sickness

  2. Malaria

  3. Kala-azar

  4. All of the above


Correct Option: D
Explanation:

  • African trypanosomiasis, also known as sleeping sickness, is an insect-borne parasitic disease of humans and other animals. It is caused by protozoa of the species Trypanosoma brucei. It is transmitted by the bite of an infected tsetse fly which acts as a vector.
  • Malaria is a mosquito-borne infectious disease affecting humans and other animals caused by Plasmodium species. The disease is most commonly transmitted by an infected female Anopheles mosquito which acts as a vector.
  • Kala-azar is a disease caused by protozoan parasites belonging to genus Leishmania. The disease is transmitted by insects which act as vectors such as sand fly.
So, the correct answer is 'All of the above'.

A biological agent of the disease is 

  1. Vitamin deficiency

  2. Virus

  3. Spores

  4. Carbohydrate deficiency


Correct Option: B
Explanation:

Biological agents which cause disease are known as pathogens that are the micro-organisms which when successfully infect the human body, multiply and produce toxins in incubation period which interfere with the normal functioning of the body and cause disease. A virus is a small, infectious, biological agent that replicates only inside the living cells of other organisms.

So, the correct answer is 'Virus'.

Which of the following human parasites require mosquito to complete their life cycle?

  1. Ascaris lumbricoides and Wuchereria bancrofti

  2. Ascaris lumbricoides and Leishmania donovani

  3. Leishmania donovani and Plasmodium ovale

  4. Plasmodium ovale and Wuchereria bancrofti


Correct Option: D
Explanation:
  • Malaria is caused by a one-celled parasite called a Plasmodium. Female Anopheles mosquitoes pick up the parasite from infected people when they bite to obtain blood needed to nurture their eggs. Inside the mosquito, the parasites reproduce and develop.
  • In Filariasis, mosquitoes can transmit the parasite, depending on the geographic area. In Africa, the most common vector is Anopheles. During a meal, an infected mosquito introduces third-stage filarial larvae onto the skin of the human host, where they penetrate into the wound. 
  • Hence, Plasmodium ovale and Wuchereria bancrofti human parasites require mosquito to complete their life cycle.
  • So, the correct answer is 'Plasmodium ovale and Wuchereria bancrofti'
 (a) Obligatory anaerobe  (i)  Fasciola hepatica 
 (b) Facultative anaerobe  (ii)  Antelope 
 (c) Polyembryony  (iii)  Ascaris lumbricoides 
 (d) Reservoir host  (iv)  Female Culex mosquito 
 (e) Biological vector  (v)  Entamoeba histolytica 

Match the following and find correct combination


  1. $a-v,b-ii,c-i,d-iii,e-iv$

  2. $a-v,b-iii,c-i,d-ii,e-iv$

  3. $a-iv,b-ii,c-i,d-iii,e-v$

  4. $a-iv,b-iii,c-i,d-ii,e-v$


Correct Option: B
Explanation:
  • Obligate anaerobes are poisoned by oxygen, so they gather at the bottom of the tube where the oxygen concentration is lowest. example: Entamoeba histolytica.
  • Facultative anaerobes can grow with or without oxygen because they can metabolise energy aerobically or anaerobically. Example: Ascaris lumoricoides. 
  • Polyembryony is the phenomenon of two or more embryos developing from a single fertilized egg. Due to the embryos resulting from the same egg, the embryos are identical to one another but are genetically diverse from the parents. An example is Fasciola hepatica.
  • Reservoir host is the host of an infection in which the infectious agent multiplies and/or develops, and on which the agent depends for survival in nature; the host is essential for the maintenance of the infection during times when the active transmission is not occurring. Examples of the reservoir host include  humans, animals, and the environment
  • Biological vectors, such as mosquitoes and ticks may carry pathogens that can multiply within their bodies and be delivered to new hosts, usually by biting.
  • So, the correct answer is 'a-v,b-iii,c-i,d-ii,e-iv'.

A fomite method of transmission of disease is through 

  1. Food

  2. Door handles

  3. Mosquitoes

  4. Soil


Correct Option: B
Explanation:

A fomite is any nonliving object or substance capable of carrying infectious organisms, such as viruses or bacteria, and hence transferring them from one individual to another. Fomites are associated particularly with hospital-acquired infections, as they are possible routes to pass pathogens between patients. Researchers have discovered that smooth (non-porous) surfaces like doorknobs transmit bacteria and viruses better than porous materials like paper money.

So, the correct answer is 'Door handles'.

A droplet infection is

  1. Tetanus

  2. Pneumonia

  3. Syphilis

  4. Typhoid


Correct Option: B
Explanation:

Pneumonia is an inflammatory condition of the lung affecting primarily the small air sacs known as alveoli. Symptoms include some combination of a productive or a dry cough, chest pain, fever, and trouble breathing. Pneumonia may spread via airborne droplets from a cough or sneeze. Pneumonia is usually caused by infection with viruses or bacteria and less commonly by other microorganisms, certain medications and conditions such as autoimmune diseases.

So, the correct answer is 'Pneumonia'.