5 DNA MODEL (deoxyribonucleic acid) Double stranded molecule with 2 sides called a helixLooks like a twisted ladder structureRungs (steps) are called bases or nucleotides. (abbreviated as A, C, T, G)Sides are made of sugar & phosphate molecules alternatingThe sugar is deoxyriboseFound in every living cell in structures called chromosomes, inside the nucleus.
7 Sugar phosphate (backbone) Phosphate moleculesDeoxyribose (sugar) moleculesNitrogenbasesNotice base pairings:A with T & C with GHydrogenbondsSugar phosphate (backbone)
8 DNA replication (copying itself) Required during growth or repair of cells.The weak hydrogen bonds are unzipped by an enzyme called DNA helicase.Free floating nucleotides from in the nucleus attach themselves to the exposed DNA strands.DNA the new bases are “glued” or fused together with DNA polymerase and the 2 new molecules of DNA are formed.
9 DNA replication (copying itself) UNZIPPED BY HELICASEDNA replication (copying itself)ACG ATG CAC___ ___ ___GTA CGT___ ___CAT GCACAT GCAGTA CGTTGC TAC GTG2 NEW DNA STRANDSCOPIES OF EACH OTHER!Glued BY polymerase
11 who contributed to the discovery of the DNA model Timeline in text pg
12 Uracil base instead of thymine DNA is also responsible in making RNA in a process called transcription.RNA will function as a template to help make proteins for the body.Remember that proteins can be structural (muscles, hair, fingernails, etc) but can also be functional in the body systems like enzymes or hormones.RNA differs from DNA in 4 main ways:Single strandedRibose sugarUracil base instead of thymineMoves out of nucleus to be functional.89basesAddAs11BpairingsSugar phosphate backbonesRNA DNARibonucleic acid deoxyribonucleic acid
13 113 forms of RNAmRNA messenger- comes out of nucleus to be the carrier of the code to make proteins. The code is read 3 bases at a time called the codon.tRNA transfer – transfers the amino acids to thegrowing protein or peptide chain- attaches to themRNA with an anticodon base pairing with the codon.rRNA ribosomal- helps the ribosomes read the code on the mRNA, so the correct amino acids are delivered in the correct order.
14 DNA MAKES RNA IN A PROCESS CALLED TRANSCRIPTION. An enzyme, RNA polymerase, separates the strands of DNA.The free floating bases in the nucleus are attracted to the bases on the DNA strand. They assemble the same as in replication except URACIL bonds with ADENINE.GTA CGT___ ___THE NEW FORMING mRNA strandACG ATG CAC___ ___ ___CAU GCATGC TAC GTGCAT GCA
15 A protein is made by a process called translation. Text pagesKnow parts and how to read the circle (mRNA & inside out)For what amino acids are part of new protein.