Download App

Human Health and Disease — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Health and Disease1 Mark
MCQ
For two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion : There is no chance of transmission of malaria to man on the bite of a male Anopheles mosquito.
Reason: It carries a non$-$virulent strain of Plasmodium.
  • A
    Both assertion and reason are true, and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true, but reason is not the correct explanation of assertion.
  • ✓
    Assertion is true, but reason is false.
  • D
    Both assertion and reason are false.
✓

Answer

Correct option: C.
Assertion is true, but reason is false.
There is no chance of transmission of malaria to man on the bite of a male Anopheles mosquito. The mouthparts of male mosquito is organised in such a manner that they cannot suck the human blood. They feed mainly on the leaf and fruit juices. Thus spreading malaria through male Anopheles is next to impossible.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Assertion (A) & Reason (B) MCQ" from Human Health and Disease→Human Health and Disease — all question types→BIOLOGY STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Name any genetically modified crop.
→
Assertion (A): Appetency is the formation of new structural or habit of the organism according to its need.
Reason (R): It is also called Lamarckian doctrine.
→
Assertion (A): Cells of tapetum have more than one nucleus.
Reason (R): They undergo meiosis without cytokinesis.
→
Assertion (A): Evolution is a continuous process that takes millions of years for speciation.
Reason (R): During evolution, small variation accumulates guided by natural selection that leads to speciation.
→
Assertion : The use of fertilizers greatly enhances crop productivity.
Reason : Irrigation is very important in increasing crop productivity.
→
Assertion (A): Fossils are remains of dead organisms.
Reason (R): Palaeontology is helpful in study of evolution.
→
For two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Sponge and Delfin are chemical methods of contraception.
Reason: Diaphragms and cervical caps are disposable barrier method of contraception.
→
Two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Bacterial cells are made competent by treating them with specific concentration of a divalent cation.
Reason: Treatment of bacterial cell with a divalent cation increases the efficiency with which $\text{DNA}$ enters the bacterium through pores in its cell wall.
→
Assertion: Statins is a blood-cholesterol lowering agents.
Reason: It inhibiting the enzyme responsible for synthesis of cholesterol.
→
Assertion $(A):$ The earliest organisms that appeared on the earth were non$-$green and presumably anaerobes.
Reason $(R):$ The first autotrophic organisms were the chemo-autotrophs that never released oxygen.
→