1. Nucleic Acids DNA vs. RNA
Chapter 12-3

2. Nucleic Acids There are 2 types of nucleic acids.
DNA
RNA
All living organisms have both DNA and RNA.
Nucleic acids are made of nucleotides.
They carry genetic information.

4. DNA vs. RNA RNA DNA Ribonucleic acid Deoxyribonucleic acid
Single-stranded
Sugar = ribose
Nucleotide Bases:
Adenine
Uracil
Guanine
Cytosine
DNA
Deoxyribonucleic acid
Double-stranded
Sugar = deoxyribose
Nucleotide Bases:
Adenine
Thymine
Guanine
Cytosine

5. DNA

6. DNA Nitrogen Bases G bonds to C A bonds to T G and A are purines
C and T are pyrimidines

7. DNA Nucleotide Structure

10. DNA Double Helix 2 strands wrapped around each other
Strands are twisted because of the bonding of pyrimidines to purines

11. DNA Double Helix Strands are oriented in opposite directions
3’ to 5’ OR 5’ to 3’

12. Function of DNA DNA contains coded instructions for making proteins.
DNA can be copied, but that does NOT explain how a gene works.
DNA contains coded instructions for making proteins.
The first step of making proteins is decoding the genetic messages by copying the nucleotide sequence from DNA into RNA.

13. RNA

14. RNA Nucleotide Structure
Ribose

16. RNA Single Helix 1 twisted strand 3 Types mRNA — Messenger RNA
tRNA — Transfer RNA
rRNA — Ribosomal RNA

17. Functions of RNA
In most cells RNA molecules have just one job — protein synthesis.
All 3 types of RNA are involved in protein synthesis.
Amino acids are the building blocks of proteins.
The assembly of amino acids is controlled by RNA.

18. mRNA
Messenger RNA serve as messengers from DNA to the rest of the cell.
They carry copies of the instructions found on genes.

19. tRNA
tRNA takes the messages from mRNA and decodes them for the ribosome.
During the construction of a protein, transfer RNA transfers each amino acid to the ribosome.

21. rRNA Proteins are assembled on ribosomes.
Ribosomes are made up of ribosomal RNA.
Ribosomal RNA helps build the actual protein.
rRNA puts together the amino acid messages carried by mRNA and decoded by tRNA.

23. DNA vs. RNA Venn Diagram
DNA
RNA
Both