Question

Which one of the following biomolecules is correctly characterised?

• A. Palmitic acid - an unsaturated fatty acid with $18$ carbon atoms.
• B. Adenylic acid - adenosine with a glucose phosphate molecule.
• C. Alanine amino acid - Contains an amino group and an acidic group anywhere in the molecule.
• D. Lecithin - a phosphorylated glycerine found in cell membrane.

Answer 1

Answer: (D)

Lecithin - a phosphorylated glycerine found in cell membrane.

Palmitic acid is a saturated fatty acid. It is mainly found in animals, plants, and microorganisms.Its chemical formula is CH${}_3$(CH${}_2$)${}_{14}$COOH.
Adenosine monophosphate (AMP), also known as 5'-adenylic acid, is a nucleotide. It is used as a monomer in DNA and RNA. It is an ester of phosphoric acid and the nucleoside adenosine. AMP consists of a phosphate group, the sugar ribose, and the nucleobase adenine.
Alanine is an -amino acid with the chemical formula CH${}_3$CH(NH${}_2$)COOH. The L-isomer is one of the 20 amino acids encoded by the genetic code. Its codons are GCU, GCC, GCA, and GCG. It is classified as a non-polar amino acid.
Lecithin is the major component of phospholipid portion of cell membrane. Thus, option D is correct and other options are wrong.
So, the correct answer is option D.