1. DNA & MODERN GENETICS DNA IS A SET OF INSTRUCTIONS FOR MAKING CELL PARTS

2. DNA & RNA ARE REQUIRED TO MAKE PROTEINS CHANGES IN DNA CAN PRODUCE VARIATION MODERN GENETICS USES DNA TECHNOLOGY

3. DNA & RNA ARE NEEDED TO MAKE PROTEINS DNA IS THE INFORMATION MOLECULE: it stores information- that’s it. RNA IS NEEDED TO MAKE PROTEIN: RNA carries data from DNA to a ribosome, where amino acids are brought together to make protein. 3 types of RNA are involved in this: messenger RNA (mRNA), ribosomal RNA (rRNA) and transfer RNA (tRNA). In eukaryotic cells RNA copies DNA data in nucleus and takes it to cytoplasm for protein synthesis.

4. DNA: Information Molecule Proteins are large molecules made up of amino acids. 23 different types join in different orders to make up thousands of different proteins found in body. DNA stores information on how to link the right amino acids in the right order to get the right protein. DNA molecule is a double stranded spiral, or twisted ladder made up of nucleotide subunits. The sides of the ladder are made of sugars & phosphates (of the nucleotide). The rung is made of 2 nitrogen bases bonding together (from 2 nucleotides)

5. DNA: continued There are 4 different nucleotides in DNA, identified by their bases: adenine (A), thymine (T), cytosine (C), and guanine (G). Bases fit together like puzzle pieces: A-T, and C- G. (All-Tigers Can-Growl) The order of bases determines the “code” for making protein. 3 nucleotide bases code for 1 amino acid (TCT codes for the amino acid arginine) some amino acids have 2- 4 different codes, all for the same amino acid. GENE: the entire sequence of bases that codes for all the amino acids in a protein.

7. DNA continued Each gene is made up a a sequence of bases at a certain spot on DNA REPLICATION: DNA being copied before a cell divides. First, the 2 strands separate by the nitrogen bases “unbonding”. Next, nucleotides in the area match up, base by base to the open DNA strand (A-T, C-G) Two identical DNA molecules are formed. During replication, DNA strand is used as a template (pattern that makes a matching product)

8. RNA NEEDED TO MAKE PROTEINS TRANSCRIPTION: process of transferring information from DNA to RNA. RNA is made up of 4 types of nucleotides also, but 1 is different. Instead of Thymine (T), RNA uses Uracil (U). Others are the same (A,C,G). During transcription, DNA is used as a template again, but to make a single strand of RNA. As DNA unzips, RNA bases match up to DNA (A-U and C-G), then RNA strand is released & moves into cytoplasm, while DNA zips back up. Many copies of RNA can be made from the same gene in a short period of time

10. RNA continued To make proteins, cells must translate the language of nucleotide bases into the language of amino acids. 3 specific bases = one amino acid TRANSLATION: the assembly of amino acids in their proper sequence. Takes place in cytoplasm & involves 3 types of RNA. Proteins are made on RIBOSOMES (made of ribosomal RNA and proteins). DNA is like cookbook, mRNA like a recipe copy, ribosome = kitchen, tRNA gathers ingredients.

11. RNA continued A tRNA molecule has 1 end that attaches to amino acid and other end has a triplet of bases to match up to triplet on mRNA. Translation starts with ribosome attaching to beginning of mRNA strand; tRNA carrying an amino acid matches up to mRNA triplet of bases. The ribosome attaches one amino acid to another as it moves along mRNA molecule; tRNA releases from mRNA after their amino acid attaches to chain of amino acids. Ribosome completes translation when it reaches end of mRNA strand; newly made protein molecule (chain of amino acids) now releases.