Assertion: BOD of a river polluted by sewage is more than 20 ppm.
Reason: Polluted river contains excess of organic matter.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
A.
If both assertion and reason are true and reason is the correct explanation of assertion.
Degree of impurity of water due to organic matter is measured in terms of BOD (Biochemical oxygen demand). BOD is the oxygen in milligrams required for five days in one litre of water at 20°C for the microorganisms to metabolise organic waste. It is measured in the milligrams of oxygen taken up in one litre of sewage. The effluent that is legally allowed to be discharged into a river or stream should be such that BOD at 20°C should not be more than 20 ppm, i.e., 20 mg per litre.
Assertion: In recombinant DNA technology, human genes are often transferred into bacteria (prokaryotes) or yeasts (eukaryotes).
Reason: Both bacteria and yeasts multiply very fast to form huge populations which express the desired gene.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Assertion: GM foods are facing widespread resistance by the people.
Reason: GM foods have mutated genes which cause infections and allergies.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Apomixis is
formation of seeds by fusion of gametes
formation of seeds without syngamy and meiosis
formation of seeds with syngamy but no meiosis
none of the above
Assertion: Parturition is induced by neural signal in maternal pituitary.
Reason: At the end of gestation period, the maternal pituitary releases prolactin which causes uterine contractions.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
An example of gene therapy is
production of injectable hepatitis B vaccine
production of vaccines in food crops like potatoes which can be eaten
introduction of gene for adenosine deaminase in persons suffering from Severe Combined Immuno Deficiency (SCID)
production of test tube babies by artificial insemination and implantation of fertilised eggs
A small rise in the body temperature of humans is corrected by
(i) sweating
(ii) dilating the skin arteries
(iii) constricting the skin arteries
(iv) increased tension of muscles in the skin
(i) only
(ii) only
(i) and (ii)
(iii) and (iv)
Assertion: Filarial worm is transmitted to humans by Culex mosquito.
Reason: Culex prefers to breed in fresh water.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Assertion: Mast cells in the human body release excessive amounts of inflammatory chemicals which cause allergic reactions.
Reason: Allergens in the environment on reaching human body stimulate mast cells in certain individuals.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Assertion: Darwin's finches are a classical example of natural selection.
Reason: Darwin explained that the difference in size and shape of the beaks of the species was a result ofthe adaptation ofthe species to different food habits.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
