2DNA deoxyribonucleic acid The code of life.Contains the code for information for an organisms growth and functionWhen a cell divides, DNA code is copied and passed to new cells.This is how the new cells receive identical coded information that was in the original cell.
3DNA Franklin Watson Crick Three scientists credited with the discovery of DNAWatson & Crick – developed the model of what DNA looked like
4DNA Double helix – twisted ladder Made up of three parts Nitrogen base : ladder rungsSugar called deoxyribose: side of the ladderPhosphate: side of the ladder
5DNA – Nitrogen bases Adenine Thymine Guanine Cytosine These bases are always pairedAdenine to ThymineGuanine to Cytosine
6DNA Bases 30% Adenine = 30 % Thymine 5% Cytosine = 5% Guanine The paired amounts must be equalEach base will only bond with its correct partner.30% Adenine = 30 % Thymine5% Cytosine = 5% Guanine
7Copying DNA Occurs BEFORE mitosis or meiosis Occurs in INTERPHASE Original DNAEnzyme separates DNA sidesNew bases pair with bases on original DNAPair with correct partner ( A-T / C-G)Two new identical DNA molecules produced
8GENES Gene – section of a DNA on a chromosome Genes – have the instructions for the making of your proteinsEach chromosome can have thousands of genesAmino acids – building blocks for proteinsGenes – determine to order of the amino acids
9Making proteins Chromosome made up of a long molecule of DNA DNA is made up of thousands of genesGene is made up of nucleotides ( three parts – sugar/base/phosphate)Nucleotide determines the type of amino acidOrder of amino acids – determines the type of protein.
10Making of Proteins DNA – stores the code for the protein DNA – locked in the nucleusProteins are made by ribosomesRibosomes are outside the nucleusSo the code from the DNA must get out of the nucleus and to a ribosomeHow does that happen?
11Making Proteins Nucleic acid – RNA ( ribose nucleic acid) RNA will get the code from the nucleus to a ribosome and then find an amino acid and build the protein.
12Types of RNA3 types of RNAMessenger RNA (mRNA)Ribosomal RNA (rRNA)Transfer RNA (tRNA)
13RNA RNA – also made of 3 parts (nucleotide) Sugar ( ribose) Phosphate Nitrogen baseRNA – singled stranded/ not twistedlike a ladder that has all its rungs sawed in half
14RNA bases Adenine Uracil Cytosine Guanine Notice they are the same as DNA EXCEPT RNA makes uracil inplace of thymine
15Messenger RNA Messenger RNA – made in the nucleus Messenger RNA carries the DNA codeFrom the nucleus to a ribosome in the cytoplasmSo messenger RNA is how the code gets out of the nucleus.This code will direct the order in which amino acids will bond. There by directing the code for a protein
16Ribosomal RNARibosomal RNA – this is the material that makes a ribosome They allow the messenger RNA carrying the code to attach.
17Transfer RNATransfer RNA are molecules of RNA found in the cytoplasm with certain amino acids attached.Transfer RNA brings these amino acids to the ribosome.
18Controlling genesCells must be able to control genes by turning some on and some off.Sometimes mistakes are made when DNA is being copied.Mutation – any permanent change in the DNA sequence of a gene or chromosomeIf DNA is not copied exactly, proteins made from the instructions might not be made correctly.
19Code Copying DNA: AAT GGG CGG TAT DNA : TTA CCC GCC ATA mRNA using DNA the top strandUUA CCC GCC UAUtRNA – AAU GGG CGG AUANotice that tRNA is almost a perfect match for the original DNA ( thymine was replaced by uracil)