Blueprints of life Discussion Question Review Question

 DNA stands for: DeoxyiriboNucleic Acid  Code that stores a cell’s hereditary material  Contains info for cell’s growth and function  DNA is copied during passed on to daughter cells during cell division BrainPop

 1952: Scientist Rosalind Franklin discovers the Double Helix  Two chains of molecules in a spiral form  Similar to a twisted ladder  Referred to as “Twisted Ladder”  Each side of the ladder is made up of sugar- phosphate molecules  Each molecule consists of the sugar called dioxyribose and a phosphate group

 The “rods” of the ladder are made up of other molecules called nitrogen bases  Nitrogen bases occur in pairs  Adenine (A)- Thymine (T)  Guanine (G) – Cytosine (C) How does DNA replicate?

 Ladder “un-zips”  Each side becomes a pattern for the new DNA strand to build off of  New DNA has bases that are identical to the original DNA Video Clip

 DNA contains “instructions” for making the proteins that determine a person’s characteristics  Gene – section of DNA on a chromosome where the instructions are found  Proteins are composed of amino acids  Genes determines the order of the amino acids  Each cell of your body only uses a portion of the thousands of genes in your DNA Where are genes found?

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 Made in the ribosomes of a cell  RNA – RiboNucleic Acid  code for making proteins

 Structure is similar to ½ of a ladder  Ribose - sugar phosphate molecule in RNA  RNA nitrogen bases occur in pairs  Adenine (A) - Uracil (U)  Guanine (G) -Cytosine (C) BrainPop

TypeDescription Messenger (mRNA) - Begins protein Synthesis - Provides code that directs sequences for amino acids Ribosomal (rRNA) - What Ribosomes are composed of Transfer (tRNA) - Serves as the “link” between mRNA and amino acids sequence of proteins

 Mutation: any permanent change in the DNA Sequence  Occurs when DNA is not copied exactly  Examples: extra chromosome, missing a chromosome  X-rays, sunlight, and some chemicals can also cause mutations BrainPop

 May or may not be life threatening  If mutation occurs in a sex cell, then all cells that form from that cell will also be mutated  Mutations add variety to species  Some mutation are harmful, some are beneficial What disease is a result of a mutation?