Question

Agarose extracted from seaweeds finds use in:
(a)Gel electrophoresis
(b)Spectrophotometry
(c)Chromatography
(d) PCR

Answer 1

Hint: Agarose is a natural linear polysaccharide obtained from red seaweeds and is used in the technique employed in the separation of DNA fragments based on the size of fragments.

Complete step-by-step answer:

Gel electrophoresis is a technique used for the separation of macromolecules based on their size and charge. A gel plate is prepared from agarose and then the wells are formed on one. Samples (usually DNA & RNA) are loaded into wells and current is applied to pull the samples through the gel and one end acquired positive charge and another negative.
Molecules migrate towards the opposite charge therefore one with a positive charge will move towards negative and vice versa. Whereas smaller particles migrate towards the gel quickly and will travel a longer distance and hence separating them according to their sizes.
-Spectrophotometry (Spectro-spectrum; photo-photons or light; metry- Quantitative analysis) is the instrument measuring the amount of light passing and absorbing through the sample.
-Chromatography is another separation technique used for isolation, purification, and analysis.
-Polymerase Chain Reaction (PCR) is a method used to amplify DNA samples.
So, the correct answer is ‘Gel electrophoresis’.

Note: -Agarose is extracted from red weed or algae having phycoerythrin and phycocyanin as their major pigments
-Agarose is preferable for DNA larger fragments separation in gel electrophoresis
-Polyacrylamide Gel is used for the separation of RNA, Smaller DNA fragments, and proteins.