Select the incorrect set of 'the typical Vector - Disease caused - Type of Pathogen'.
- A.Aedes - Chikungunya - Bacteria
- B.Culex - Lymphatic Filariasis - Parasite
- C.Anopheles - Malaria - Parasite
- D.Aedes - Dengue - Virus
Correct answer
Explanation
The correct answer is A, Aedes - Chikungunya - Bacteria. This set is wrong because chikungunya is caused by a virus, the chikungunya virus, and not by bacteria. It is spread by Aedes mosquitoes, the same day-biting mosquitoes that carry dengue and Zika, and it causes high fever with severe joint pain. The name comes from a word in the Makonde language of East Africa meaning 'that which bends up', describing patients bent over with pain. Aedes breeds in clean water stored in coolers, tyres, pots and tanks, which is why dengue and chikungunya cases rise after the monsoon. Option B is a correct set because the Culex mosquito spreads lymphatic filariasis, or elephantiasis, caused by parasitic worms such as Wuchereria bancrofti. Option C is correct because the female Anopheles mosquito spreads malaria, caused by the Plasmodium parasite, a protozoan. Option D is correct because Aedes also spreads dengue, which is caused by the dengue virus. Exam tip: Aedes carries dengue, chikungunya and Zika, all viruses; Anopheles carries malaria; Culex carries filariasis and Japanese encephalitis.
Practice Questions
View allThe fact that the planets move around the Sun, not in circles but in ellipses, was first demonstrated by
- A.Galileo
- B.Martin Luther
- C.Johannes Kepler
- D.Copernicus
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In 1609 Kepler showed that the planets move around the Sun in elliptical orbits, with the Sun at one focus of the ellipse.
Read the full explanation →Which one of the following statements is correct?
- A.Urea is produced in liver.
- B.Urea is produced in blood.
- C.Urea is produced from digestion of starch.
- D.Urea is produced in lung and kidney.
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Liver cells turn the toxic ammonia released from the breakdown of amino acids into urea through the ornithine cycle, also called the urea cycle.
Read the full explanation →Which one of the following is the correct sequence of passage of light in a compound microscope?
- A.Condenser-Objective lens-Eyepiece-Body tube
- B.Objective lens-Condenser-Body tube-Eyepiece
- C.Condenser-Objective lens-Body tube-Eyepiece
- D.Eyepiece-Objective lens-Body tube-Mirror
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Light passes through the condenser to the specimen, is picked up by the objective lens, travels up the body tube and reaches the eye through the eyepiece.
Read the full explanation →Which one of the following statements regarding haemoglobin is correct?
- A.Haemoglobin present in RBC can carry only oxygen but not carbon dioxide.
- B.Haemoglobin of RBC can carry both oxygen and carbon dioxide.
- C.Haemoglobin of RBC can carry only carbon dioxide.
- D.Haemoglobin is only used for blood clotting and not for carrying gases.
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It binds oxygen at its iron-containing haem groups and carries some carbon dioxide on its protein chains. Each haemoglobin molecule has four polypeptide chains and four haem groups, and each haem iron can hold one oxygen molecule, forming oxyhaemoglobin in the lungs.
Read the full explanation →Which one of the following statements regarding histone proteins is correct?
- A.Histones are proteins that are present in mitochondrial membrane.
- B.Histones are proteins that are present in nucleus in association with DNA.
- C.Histones are proteins associated with lipids in the cytosol.
- D.Histones are proteins associated with carbohydrates in the cytosol.
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They are the proteins around which DNA winds to form chromatin in the nucleus of eukaryotic cells. Histones are small basic proteins, rich in the positively charged amino acids lysine and arginine, which attract the negatively charged phosphate groups of DNA.
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