Advertisements
Advertisements
प्रश्न
Answer the following question in your own words.
Describe the structure of the DNA molecule.
उत्तर
- All organisms have the same DNA structure. Watson and Crick modelled DNA in 1953. In this model, two parallel nucleotide threads coil around each other. A ‘double helix’ describes this arrangement. Like a coiled ladder, its construction is flexible.
- The DNA strands include many tiny ‘nucleotide’ molecules. Four nitrogenous bases are adenine, guanine, cytosine, and thymine. Cytosine and thymine are pyrimidines and adenine and guanine are purines.
- A nitrogenous base, phosphoric acid, and sugar molecule form the nucleotide.
- Four types of nitrogenous bases equal four types of nucleotides.
- DNA has a chain of nucleotides. Each ladder rail is constructed of alternately connected sugar and phosphoric acid molecules, like the DNA molecule's two threads. Every ladder step is two nitrogenous bases connected by hydrogen bonds. Adenine always connects with thymine, cytosine with guanine.
Structure of DNA
DNA (Watson and Crick’s Model)
APPEARS IN
संबंधित प्रश्न
Name the enzyme and state its property that is responsible for continuous and discontinuous replication of the two strands of a DNA molecule
The three sketch (A, B and C) are intended to represent the replication of DNA.
What should be their correct sequence, starting with the first and ending with the last? ……
Fill in the blank:
DNA replicates in the ______ of the cell cycle.
State whether the following sentence is true or false:
Genes are arranged in a linear order on a chromosome.
State whether the following sentence is true or false:
In any specimen of DNA, the total molar amount of A + G = T+ C.
Choose the correct answer:
This structure is not present in all chromosomes ___________
Give Technical Term:
The individual having similar pair of genes.
Complete the following sentence with appropriate word:
A chromosome is composed of 50 % DNA and 50% ________.
Multiple Choice Question
DNA structure was discovered by:
Multiple Choice Question:
In the RNA molecule, which nitrogen base is found in place of thymine?
Name the bond which binds the nucleotides in a DNA.
How is the structure of DNA organized?
What is the biological significance of DNA?
A nucleoside differs from a nucleotide in not having a ______.
