DNA DNA Structure Video Clip DNA is the genetic information of all living things. It is stored in the nucleus of every cell and is organized into chromosomes. The information on DNA is determined by the sequence of a 4 “letter” alphabet. Similarly, English stores and transfers information with the English Language made up of 26 letter and computers use binary code with ones and zeros. DNA has a protective structural backbone with information stored inside, like a book has a cover and pages. DNA Structure Video Clip

DNA Deoxyribonucleic acid Type of nucleic acid What chromosomes (and genes) are made of Made of repeating nucleotide subunits

DNA Structure Complementary Nitrogen Base Pairs Double Helix Nucleotide DNA is the genetic information of all living things. DNA is found in the nucleus of cells and organized into chromosomes. DNA is in a double helix structure, meaning it is 2-sided and twisted. DNA is made up of many nucleotides; one nucleotide contains a phosphate, a sugar and a nitrogenous base. The Backbone of the DNA is made of Phosphate and Sugar gives the DNA its structure. The Information on DNA is determined through the sequence of Nitrogenous Bases located in between the 2 backbones. There are 4 Nitrogenous bases: Adenine, Thymine, Guanine and Cytosine. Adenine and Thymine always bond to each other and Guanine and Cytosine always bond with each other; this is called complementary base pairing. Backbone

DNA Structure DNA is in a double helix structure, meaning it is 2-sided and twisted. DNA is made up of many nucleotides; one nucleotide contains a phosphate, a sugar and a nitrogenous base. The Backbone of the DNA is made of Phosphate and Sugar gives the DNA its structure.

DNA Structure The Information on DNA is on the Nitrogen Bases in between the 2 backbones. There are 4 Nitrogen bases: Adenine, Thymine, Guanine and Cytosine. Adenine and Thymine always bond and Guanine and Cytosine always bond; this is called complementary base pairing.

Shape of DNA Double helix: 2 spirals wound around each other

Rosalind Franklin x-ray diffraction image of DNA Confirming helical structure of DNA

James Watson and Francis Crick Interpreted the photo and discovered the double helix structure They won a Nobel Prize

Protein Synthesis DNA Transcription and Protein Assembly - YouTube

Replication Process by which DNA copies itself DNA Polymerase Enzyme- helps proof read each DNA strand chromosomes copy themselves before mitosis and meiosis Each new piece of DNA is made up of 1 old strand and 1 new strand

Replication DNA never leaves the nucleus DNA is the master copy of the directions a cell needs to live so it needs to be protected.

Transcription RNA is a copy of DNA RNA: Ribonucleic acid Go into cytoplasm RNA Polymerase RNA: Ribonucleic acid You can always make more RNA, but not DNA How does it know where to copy? Promoters- specific base sequences in the DNA

Transcription RNA is made from 1 gene in DNA The type of RNA made is called mRNA (messenger RNA) Sends message from DNA to the cytoplasm

Translation mRNA leaves nucleus mRNA attached to a ribosome tRNA decodes the mRNA and brings amino acids to build the protein Protein detaches from ribosomes

Where does Translation occur? On the ribosomes