Assertion: Deficiency of sulphur causes chlorosis in plants.
Reason: Sulphur is a constituent of chlorophyll, proteins and nucleic acids.
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.
C.
If Assertion is true but Reason is false
Mechanistically, iron and/or sulfur are highly reactive components of many enzymes. Indeed, iron and sulfur sometimes form Fe2S2, Fe3S4, or Fe4S4 clusters which are very active electron transfer agents. Recently, iron‐sulfur clusters have been reported to serve as sensors of oxidative stress, to couple photosynthesis with several metabolic pathways, to participate in the reduction of sulfite and nitrite, and to participate in regulation of gene expression. Thus, there are several mechanisms by which a deficiency of nitrogen, sulfur, or iron could produce the same low‐chlorophyll, yellow phenotype in plants.
