Cell

Polynucleotide chain of DNA contains

[amp_mcq option1=”a nitrogenous base, deoxyribose sugar and phosphate group” option2=”a nitrogenous base, ribose sugar and phosphate group” option3=”deoxyribose sugar, ribose sugar and phosphate group” option4=”a nitrogenous base and phosphate group only” correct=”option1″]

A polynucleotide chain of DNA is a polymer made up of repeating units called nucleotides. Each DNA nucleotide consists of three components: a nitrogenous base (Adenine, Guanine, Cytosine, or Thymine), a deoxyribose sugar (a five-carbon sugar lacking an oxygen atom at the 2′ position), and a phosphate group. These nucleotides are linked together by phosphodiester bonds between the sugar of one nucleotide and the phosphate group of the next.

Understanding the basic building blocks of DNA (nucleotides) and their components is fundamental to molecular biology.

RNA differs from DNA in that it contains ribose sugar instead of deoxyribose sugar and the nitrogenous base Uracil (U) instead of Thymine (T). Both DNA and RNA contain Adenine (A), Guanine (G), and Cytosine (C).

The living content of a cell is called protoplasm. It is composed of :

[amp_mcq option1=”Cytoplasm only” option2=”Cytoplasm and nucleoplasm” option3=”Nucleoplasm only” option4=”Cytoplasm, nucleoplasm and other organelles” correct=”option4″]

The living content of a cell (protoplasm) is composed of cytoplasm and nucleoplasm.

– Protoplasm refers to all the living substance within a cell membrane.
– In eukaryotic cells, protoplasm includes the cytoplasm (the material within the cell membrane but outside the nucleus) and the nucleoplasm (the substance within the nucleus).
– Cytoplasm itself consists of the cytosol (the jelly-like substance) and the organelles suspended within it. Nucleoplasm contains the genetic material (DNA) and other components of the nucleus.

Option D is redundant because “other organelles” are already included within the definition of cytoplasm. The standard biological definition of protoplasm in a eukaryotic cell is cytoplasm plus nucleus (or cytoplasm and nucleoplasm, which constitutes the living content of the nucleus). Option B accurately reflects this fundamental division within the cell.