The Salk Mobile Science Lab Welcome Back!

What is DNA? Deoxyribo-Nucleic Acid Long molecule made of different chemicals called Adenine, Thymine, Guanine, and Cytosine -Ask students to tell you what they know about DNA to gauge the audience and use responses to dictate how you go through these slides -Ask students to say the full name of DNA together on the count of 3 -PAUSE ON 2nd DNA diagram to discuss "What do you notice about this diagram?" etc. ATGCCTAAGTACCGTATA

What is DNA? Deoxyribo-Nucleic Acid Long molecule made of different chemicals called Adenine, Thymine, Guanine, and Cytosine Shaped like a twisted ladder Double Helix

What is DNA? Deoxyribo-Nucleic Acid Career Spotlight! Molecular Geneticists study the structure of DNA involved in different diseases Deoxyribo-Nucleic Acid Long molecule made of different chemicals called Adenine, Thymine, Guanine, and Cytosine Shaped like a twisted ladder Double Helix

How is DNA organized? nucleus genome chromosome DNA gene Gauge the audience- Has anyone ever seen a diagram like this? Can you name any structures? Nucleus holds all the genetic info All of your genetic info is your "genome" Broken down into chromosomes A single instruction is called a gene, All of this material is composed of DNA gene

What does DNA do? Your DNA determines your PHENOTYPE Instruction book for your cells MY DNA hair shape body skin eyes The cells in your eye have the same DNA as the cells in your skin, but they have different jobs. Depending on which "pages" or genes a cell uses will give it different characteristics How your cells read your Genome(all of your DNA) depends in part on your (and your cells’) environment

What does DNA do? Each instruction is called a GENE Genes are the recipes for Proteins All your genes together is called your GENOME Let's go over an example on how cells do this...

Reading DNA PORFAVORNOHABLECUANDOESTOYHABLANDO. ATACGGGCTAGCCTGACGTCAGTTTAAAAGCCCTG. -Ask students to not shout out, ask for 1 student volunteer -What did you need to do so I could understand this instruction?

Reading DNA TGACGTAAAGCTTGACCTA PUT A HAT ON YOUR HEAD PUT A BAT ON YOUR HEAD TGACATAAAGCTTGACCTA PUT A BAT ON YOUR HEAD MUTATION! Get two student volunteers! Ask students to give volunteers a round of applause once the word “mutation” appears so they can go back to their seats. Make connection between this example and the fruit flies they observed on day 1

Reading DNA MUTATIONS are changes in your GENES that may be inherited PUT A HAT ON YOUR HEAD PUT A BAT ON YOUR HEAD MUTATION! MUTATIONS are changes in your GENES that may be inherited Even small changes in DNA can have big effects Human DNA is ALL >99% identical! Get two student volunteers! Ask students to give volunteers a round of applause once the word “mutation” appears so they can go back to their seats. Make connection between this example and the fruit flies they observed on day 1

Reading DNA MUTATIONS are changes in your GENES that may be inherited Career Spotlight! Genetic Counselors help people figure out if they might pass a disease mutation to their future children PUT A HAT ON YOUR HEAD PUT A BAT ON YOUR HEAD MUTATION! MUTATIONS are changes in your GENES that may be inherited Even small changes in DNA can have big effects Human DNA is ALL >99% identical! Recall that not all mutations are bad

} DNA found in nucleus (Eukaryotic) Where is DNA? DNA is found in the cells of every living organism There are different types of cells Animal cells Plant cells Bacteria cells } DNA found in nucleus (Eukaryotic) - DNA floating loose (Prokaryotic) What are the 3 types of cells? If students are stuck, ask “What types of cells makes dogs, zebras, and humans? What types of cells makes roses, broccoli or elm trees? What types of cells are found in yogurt, your gut and sometimes can make you sick?” Ask students if they know any of the structures of animal cells or plant cells- if not, review: cell membrane, cell wall, nucleus, and DNA, but mention there are many more structures

What color is DNA?

So how can scientists tell different DNA apart? If everything has DNA, why is life so diverse? If all DNA is white, what are some challenges you think scientists would face? What could they do if they wanted more information about the DNA?

Scientists use DNA extraction in the lab every day: What do scientists do with DNA? Scientists use DNA extraction in the lab every day: To find out if a patient has a mutation that might cause a disease To see if one of their model organisms has the gene they want to study We can even use the DNA to change cells by taking DNA from one organism and putting it into another! When the scientists extract the dna, they can then find out what it says in order to… Point 3: Remember the hat demonstration… the two volunteers ended up looking different because we gave them different instructions. If we give instructions to a cell that did not have them before, it will end up looking different!

What would happen if… Fluorescent Rabbit ! Rabbit Fluorescent Jellyfish We took the DNA from a fluorescent jelly fish- its DNA has instructions that tell it how to be fluorescent And put it into a bunny rabbit?

Scientists can make all sorts of fluorescent organisms Remember our friends from yesterday?!!!

We can even look at where things are inside of living cells! These are pictures of cells- remember the nucleus in the middle (which is blue) By looking under a special microscope for the green fluorescent protein, the scientist can see where something is located, kind of like a tracking devise or the lights they have on airplanes and boats so you can see where they are at night. On the left the green is in the cytoplasm, like all the beads in the models on your table. On the right the green is on outer membrane. So scientists can use DNA for all sorts of things!

Scientists do all sorts of cool things with DNA… What will you do with your DNA??? Take it home Have your parents guess what it is Tell them what it is and what you did in class today!