1. DNA Replication
Living Environment 2015

2. DNA Replication
Each strand of DNA has the information needed to reconstruct the other half.
To create new strands the DNA uses something called base pairing.

3. Base Pairing During replication the DNA “unzips” to form two strands.
DNA bases are present in the cell. These bases match up with the “unzipped” strands.
C matches with G, A matches with T

5. Replication
There are enzymes, called polymerase, that “unzip” the DNA.
Each of the molecules produced contains one new strand of DNA and one old strand.

6. RNA and Protein Synthesis

7. What is RNA?
Ribonucleic Acid
Helps the DNA to produce proteins

8. How is RNA different from DNA?
RNA contains the sugar ribose
RNA does NOT contain the base Thymine
Uracil replaces thymine
RNA is single stranded

9. Transcription
This is the process where DNA is used as a template to produce RNA
DNA “unzips” and RNA bases attach to form a strand of RNA

10. Transcription
This strand detaches itself from the DNA and can leave the nucleus
This type of RNA is referred to as messenger RNA (mRNA)

11. Translation This is the process where mRNA is brought to the ribosomes
Transfer RNA (tRNA) has amino acids attached to it
tRNA attaches to the mRNA forming a chain of amino acids

13. Amino Acids
Every amino acid is coded by a sequence of three bases, called a codon
The string of amino acids produced during translation forms a protein that can then be released into the cell for it’s use
The stop codons are UGA, UAG, UAA

14. Vocabulary:
Replication - Synthesis of an identical copy of a DNA strand.
Transcription - Synthesis of mRNA molecule.
Translation - Synthesis of polypeptide from amino acids.
Codon - Base triplet on mRNA.
Anticodon - Complementary triplet on tRNA.
Polypeptide - Protein molecule