Transcript Slide 1
Do the cells in your eye and your tongue have the same functions? Do the cells in your eye and your tongue have the same proteins? Do the cells in your eye and your tongue have the same DNA? Humans have 46 chromosomeswhere are they? • Do all cells have DNA? • Do all cells have the same DNA? When doing DNA identification (think CSI) does it matter which cells you use to get the sample? Cheek cells? Blood cells? Hair follicle cells? What changes occur to a salmon when it spawns? Do the salmon’s proteins change when it spawns? Does a salmon’s DNA change when it spawns? Does the DNA in your body change as you go through puberty? Does the DNA in your body change as you go through puberty? Questions 1. Do different cells in your body have different DNA? 2. What makes you think that? 3. Does the DNA in your cells change as you develop from a baby to an adult? 4. What makes you think that? What have we learned? • Proteins determine most characteristics of a cell and organism • Information stored in DNA determines which proteins can be made by a cell • The environment influences which proteins are made by a cell Some things we will learn… • Where is protein made in a cell? • How does the information stored in DNA determine which proteins can be made in a cell? • How is protein made in a cell? • How does the environment influence which proteins are made in cell? Where is protein made in a cell? DNA does not leave the nucleus of eukaryotic cells... but proteins are made outside of the nucleus by ribosomes human cheek cell Elodea leaf cell mitochondria chloroplasts vacuole nucleus (DNA here) (DNA here) DNA does not leave the nucleus of eukaryotic cells... but proteins are made outside of the nucleus by ribosomes ribosomes (proteins made here) (proteins made here) nucleus (DNA here) (DNA here) DNA and ribosomes are at different locations in a prokaryoic cell. E. coli bacteria cell ribosomes (proteins made here) DNA Information flow from DNA to trait DNA Stored in nucleus protein Made by ribosomes outside of nucleus Observed trait messenger RNA • mRNA transfers information from the DNA in the nucleus to the ribosomes. • Ribosomes build proteins according to the mRNA information received. Information flow from DNA to trait DNA Stored in nucleus messenger RNA protein Made by ribosomes outside of nucleus Observed trait DNA information mRNA information DNA messenger RNA Transcription is the process used to convert DNA information into mRNA information. Note: DNA does not become RNA; the information in DNA is copied as RNA