Biology 6.0
DNA/Protein Synthesis
Structure of DNA:
Monomer = __________________________
Composed of three parts:
1.
2.
3.
Nitrogen Bases:
A. Purines
1.
2.
B. Pyrimidines
1.
2.
Base Pairing Rules:
1.
2.
Antiparallel Nature of the DNA – (why?)
Replication of a DNA molecule
Due to the fact that A always pairs with T and G always pairs with C. If one side of a
DNA strand is given, the other side can be determined. Each strand of DNA is said to
be _______________________ to the other strand.
To simplify a diagram of DNA, only the sequence of nitrogen bases are labeled,
since all nucleotides are composed of a phosphate group and deoxyribose. Draw an
example below:
Process of DNA replication
1. Separate the DNA strands using an enzyme known as helicase.
2. Addition of new nucleotides to the exposed single stranded DNA molecule using
an enzyme DNA polymerase. DNA polymerase may only add nucleotides in a 5’ to 3’
direction.
Leading Strand –
Lagging Strand –
Okazaki Fragment –
Identify the leading and lagging strand….
Semi conservative Replication
versus
Structure of RNA
Monomer = _______________________
Composed of:
1.
2.
3.
Differences between DNA and RNA:
1.
Conservative Replication
2.
3.
Types of RNA:
1.
2.
3.
Protein Synthesis –
Two Steps:
1.
2.
TRANSCRIPTION – The conversion of ________ to ________.
RNA Polymerase –
Codons –
Translation – Conversion of ________ to ________.
Structure of a tRNA molecule:
Our simplified diagram
Contributors to the Genetic Code:
1. Rosalind Franklin
2. James Watson and Francis Crick
3. Erwin Chargaff
Prokaryotic Gene Regulation
Operator
Promoter
Structural Genes
OPERON
Eukaryotic Gene Expression