Biological Molecules - DNA, RNA and DNA Replication Flashcards
What is the function of DNA?
To hold genetic information
What are the components of a DNA nucleotide?
A deoxyribose sugar, a phosphate group and a nitrogen containing base.
What are the bases in DNA?
Adenine, cytosine, guanine and thymine.
What is the function of RNA?
To transfer genetic information from DNA to the ribosomes for protein synthesis.
What are the components of an RNA nucleotide?
A ribose sugar, a phosphate group and a nitrogen-containing base.
What are the bases in RNA?
Adenine, cytosine, guanine and uracil.
How are the nucleotides of RNA/DNA joined together?
By phosphodiester bonds formed in a condensation reaction. The bond forms between the sugar of one nucleotide and the phosphate group of another.
Give the structure of a DNA molecule.
A double helix with a phosphodiester backbone composed of two strands of DNA nucleotides joined together by hydrogen bonds between complementary bases.
Give the structure of an RNA molecule.
A short polyneucleotide chain.
Give the structure of an RNA molecule.
A short polyneucleotide chain.
Which bases of DNA are complementary?
Adenine-thymine
Guanine-cytosine
Why is DNA a stable molecule?
- The phosphodiester backbone protects the more chemically bases inside the double helix
Outline the process of semi-conservative DNA replication.
- DNA helicase breaks the hydrogen bonds between complementary bases, causing the DNA strands to separate.
- Each strand is used as a template and complementary bases pairing occurs between the template strand and free nucleotides.
- DNA polymerase joins the together by forming phosphodiester bonds.
What is the result of DNA replication?
Two identical strands of DNA are formed.
