Question

The basic/ structural unit of a nucleic acid is-
A. Pentose sugar
B. Nucleoid
C. Nucleoside
D. Nucleotide

Answer 1

Hint: Cell organelles as we know are the components of a cell. They are useful for performing different activities of the cell just like the organ system in the body. Cells perform different activities like- cell repair, blood formation, repair damaged tissues etc. Cells are the vital structures of life. Nucleic acid is present inside the nucleus.

Complete answer-
Option A: Pentose sugar- sugars present in nucleic acid is- ribose or deoxyribose. Ribose is the sugar base of RNA and deoxyribose is the sugar base in DNA.
Option A is not the correct answer.
Option B: Nucleoid- nucleoid contains genetic material and it is from a prokaryotic cell. Unlike eukaryotic cells they do not have any surrounding membrane.
Option B is not the correct answer.
Option C: Nucleoside- nucleoside with pentose sugar addition is called nucleotide. Sugar bases that are ribose and deoxyribose removal from nucleotides are called nucleosides.
Option C is not the correct answer.
Option D: Nucleotide- adenine, guanine, thymine and cytosine which are present in DNA and in RNA the thymine is replaced by uracil are the nucleotides. Nucleotides consist of sugar base and nitrogen base.
Option D is the correct answer.

Therefore, Option D is correct.

Note:
As we discussed various organelles. Eukaryotic and prokaryotic organelles are \[80\]S and \[70\]S. ribosomes are the headquarters for the polypeptide synthesis. Hence, polypeptides are the building blocks of our body. And as cells are multicellular structures. So, it helps in all vital components in our bodies. Nucleic acid is the major component of DNA.