Question

What is a "strand" of DNA?

How many strands make up a DNA double helix?

Each strand is made up of two zones or regions. ...

What holds one strand against the other in the double helix?

How do cells make accurate copies of DNA?

When do cells duplicate their DNA?

What information is coded into DNA?

What is a "codon"?

Answer 1

 Every generation of each and every species resembles its ancestors in many ways.

How are these characteristics transmitted from one generation to the next?

 It has been observed that nucleus of a living cell is responsible for this transmission

of inherent characters, also called heredity.

 The particles in nucleus of the cell, responsible for heredity, are called chromosomes

which are made up of proteins and another type of biomolecules called nucleic

acids.

 Nucleic acids are responsible for the transfer of characters from parents to off

springs. There are two types of nucleic acids — DNA and RNA.

 A nucleic acid containing deoxyribose is called deoxyribonucleic acid (DNA) while that

which contains ribose is called ribonucleic acid (RNA).

 Both DNA and RNA contain Adenine, Guanine and Cytosine. The fourth base is

Thymine in DNA and Uracil in RNA.

 The structure of DNA is a double strand [helix] whereas RNA is a single strand

molecule.

 Hydrogen bonds bind the nitrogenous bases of the two separate polynucleotide