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Nucleic Acids DNA vs. RNA. Chapter 12-3. 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. DNA Deoxyribonucleic acid Double-stranded Sugar = deoxyribose
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Nucleic AcidsDNA vs. RNA Chapter 12-3
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.
DNA Deoxyribonucleic acid Double-stranded Sugar = deoxyribose Nucleotide Bases: Adenine Thymine Guanine Cytosine RNA Ribonucleic acid Single-stranded Sugar = ribose Nucleotide Bases: Adenine Uracil Guanine Cytosine DNA vs. RNA
DNA Nitrogen Bases • G bonds to C • A bonds to T • G and A are purines • C and T are pyrimidines
DNA Double Helix • 2 strands wrapped around each other • Strands are twisted because of the bonding of pyrimidines to purines
DNA Double Helix • Strands are oriented in opposite directions • 3’ to 5’ OR 5’ to 3’
Function of DNA • 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.
RNA Nucleotide Structure Ribose
RNA Single Helix • 1 twisted strand • 3 Types • mRNA — Messenger RNA • tRNA — Transfer RNA • rRNA — Ribosomal RNA
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.
mRNA • Messenger RNA serve as messengers from DNA to the rest of the cell. • They carry copies of the instructionsfound on genes.
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.
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.
DNA RNA Both DNA vs. RNA Venn Diagram