Given below are two statements one is labelled as Assertion A and the other is labelled as Reason R: Assertion A: In size exclusion chromatography,…
Given below are two statements one is labelled as Assertion A and the other is labelled as Reason R:Assertion A: In size exclusion chromatography, larger proteins elute earlier and smaller proteins elute later.Reason R: When matrices like sephadex are used, the partitioning of protein molecules between liquid and solid phases is a function of protein size.In the light of the above statements, choose the correct answer from the options given below:
Select an option to attempt
Correct Answer: Option A
Explanation
Size exclusion chromatography (SEC): both statements correct:Size exclusion chromatography (also called gel filtration) separates proteins by molecular size:• Larger proteins: EXCLUDED from the pores of the gel beads → travel only through the void volume → ELUTE FIRST (shorter retention time).• Smaller proteins: ENTER the pores → take longer to traverse the column → ELUTE LATER.Statement A: 'Larger proteins elute first in SEC' — TRUE ✔Statement R: 'Separation is size-dependent because proteins partition between the stationary (pore) phase and the mobile (interstitial) phase' — TRUE, and this correctly EXPLAINS statement A. ✔This is an Assertion-Reason question where BOTH are true and R is the correct explanation of A.Answer: Both A (large molecules elute first) and R (partitioning is size-dependent) are correct; R explains A.