CENTRAL DOGMA OF MOLECULAR BIOLOGY
The central dogma of molecular biology, first described by Francis Crick in 1958, describes
the flow of genetic information within a biological system. It states that the genetic information
is transferred from DNA to RNA to protein explaining how genetic instructions make
functional products.
The three main processes consisting of these following steps:
Replication: DNA copies itself to ensure genetic information is passed on.
Transcription: Information in DNA is copied into messenger RNA (mRNA).
Translation: mRNA is used to synthesize proteins (amino acid sequences).
DNA Replication
DNA replication is a key biological process that copies a cell's genetic material before the cell
splits. This ensures that each new cell gets a complete and exact copy of the DNA. The process
is called semiconservative because each new DNA molecule has one part from the original
DNA and one part that is built new. The original part acts as a guide to make sure the new DNA
is copied correctly.
Enzymes Involved in DNA Replication
DNA replication is a complex process which involves a number of enzymes to unzip, copy, and
seal DNA strands. Key enzymes include Helicase (unwinds the helix), Primase (creates RNA
primers), DNA Polymerase (synthesizes new DNA), Topoisomerase/Gyrase (relieves strain),
and DNA Ligase (joins fragments).
(a) Helicase: Plays a major role to create the replication fork by breaking downthe
hydrogen bonds between base pairs to unzip the double helix.
(b) DNA Polymerase (I, II, III): Three types of DNA Polymerases, of which DNA
Polymerase III which is the primary enzyme in prokaryotes, responsible for
synthesizing new DNA strands by adding nucleotides in the 5' to 3' direction. The DNA
Polymersase Delta and Epsilon is the main polymerases found in eukaryotes.
(c) DNA Polymerase I: Removes RNA primers and fills in the gaps with DNA.
(d) Primase: Allows to generate short RNA primers which act as a starting point for DNA
polymerase.
The central dogma of molecular biology, first described by Francis Crick in 1958, describes
the flow of genetic information within a biological system. It states that the genetic information
is transferred from DNA to RNA to protein explaining how genetic instructions make
functional products.
The three main processes consisting of these following steps:
Replication: DNA copies itself to ensure genetic information is passed on.
Transcription: Information in DNA is copied into messenger RNA (mRNA).
Translation: mRNA is used to synthesize proteins (amino acid sequences).
DNA Replication
DNA replication is a key biological process that copies a cell's genetic material before the cell
splits. This ensures that each new cell gets a complete and exact copy of the DNA. The process
is called semiconservative because each new DNA molecule has one part from the original
DNA and one part that is built new. The original part acts as a guide to make sure the new DNA
is copied correctly.
Enzymes Involved in DNA Replication
DNA replication is a complex process which involves a number of enzymes to unzip, copy, and
seal DNA strands. Key enzymes include Helicase (unwinds the helix), Primase (creates RNA
primers), DNA Polymerase (synthesizes new DNA), Topoisomerase/Gyrase (relieves strain),
and DNA Ligase (joins fragments).
(a) Helicase: Plays a major role to create the replication fork by breaking downthe
hydrogen bonds between base pairs to unzip the double helix.
(b) DNA Polymerase (I, II, III): Three types of DNA Polymerases, of which DNA
Polymerase III which is the primary enzyme in prokaryotes, responsible for
synthesizing new DNA strands by adding nucleotides in the 5' to 3' direction. The DNA
Polymersase Delta and Epsilon is the main polymerases found in eukaryotes.
(c) DNA Polymerase I: Removes RNA primers and fills in the gaps with DNA.
(d) Primase: Allows to generate short RNA primers which act as a starting point for DNA
polymerase.
