Assertion (A): Methemoglobinemia is a condition in which blood is not able to carry and deliver enough oxygen to the body.
Reason (R): Consuming drinking water with high nitrate levels may cause methemoglobinemia.
Choose the correct answer from the options given below:
Both (A) and (R) are true and (R) is the correct explanation of (A).
This is an Assertion-Reason item and both statements must be judged for truth, and then whether the reason correctly explains the assertion.
The Assertion states that methemoglobinemia is a condition in which blood is unable to carry and deliver enough oxygen to the body. This is true. In methemoglobinemia, normal haemoglobin is converted into methemoglobin, a form in which iron is in the ferric state and cannot bind and release oxygen effectively, so oxygen delivery to body tissues is impaired (this is the basis of the bluish skin seen in the so-called blue baby syndrome in infants).
The Reason states that consuming drinking water with high nitrate levels may cause methemoglobinemia. This is also true. Excess nitrate in drinking water, often from fertilizer runoff or contaminated groundwater, is converted to nitrite in the body; nitrite oxidizes haemoglobin into methemoglobin, and this is the principal cause of nitrate-induced blue baby syndrome, especially in bottle-fed infants.
Crucially, the Reason directly explains the Assertion: high nitrate intake is the very mechanism that produces the oxygen-carrying failure described in the Assertion. Therefore both statements are true and the Reason is the correct explanation of the Assertion.
The option saying the Reason is not the correct explanation is wrong because the nitrate mechanism is precisely what produces the condition. The options claiming either statement is false are wrong because both are established facts.
Correct answer: Both (A) and (R) are true and (R) is the correct explanation of (A).
Similar Questions
Given below are two statements:
Statement I: Some people suffer from what is called as Sick Building Syndrome (SBS).
Statement II: SBS is caused due to supply of polluted water in a particular building.
In the light of the above statements, choose the most appropriate answer from the options given below:Match List I with List II
LIST I (Hazardous substance) LIST II (Specific effect) A. Neurotoxins I. Substances that cause cancer. B. Mutagens II. Substances that attack nerve cells. C. Teratogens III. Substances that damage or alter genetic material (DNA) in cells. D. Carcinogens IV. Substance that cause abnormality during embryonic growth and development. Choose the correct answer from the options given below:
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Schistosomiasis, a common water contact disease, is spread by which of the following?
Important Questions from Impact of Pollutants on Human Health
Which of the following pollutants is included in the Air Quality Index in India?
Blue-baby syndrome can happen due to the excess of which component in the water?
Match List I with List II
List I
List II
Emitted Pollutants
Environmental Impact
A. Carbon dioxide
I. Formation of acid rain
B. Carbon monoxide
II. Toxic and are carcinogenic
C. Nitrogen oxides
III. Toxic and can cause
respiratory diseases
D. Benzene and
hydrocarbon
IV. Contribution to global warming
as a Greenhouse gas
Choose the correct answer from the option given below:
Given below are two statements:
Statement I: Dioxins and furans are highly toxic substances produced mainly during incineration of municipal solid waste, hazardous and medical wastes.
Statement II: Dioxins and furans play a crucial role in photochemical smog formation.
In the light of the above statements, choose the correct answer from the options given below:
Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R) :
Assertion (A): Carbon monoxide (CO) is a serious asphyxiant even a short exposure may have fatal health issues.
Reason (R): Hemoglobin present in the blood has a greater affinity towards carbon monoxide than oxygen.In the light of the above statements choose the most appropriate answer from the options given below :
