DNA Structure Video Clip DNA Deoxyribonucleic acid Type

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 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 You. Tube

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 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 – 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 m. RNA (messenger RNA) – Sends message from DNA to the cytoplasm

Translation • m. RNA leaves nucleus • m. RNA attached to a ribosome • t. RNA decodes the m. RNA and brings amino acids to build the protein • Protein detaches from ribosomes

Where does Translation occur? • On the ribosomes