Objective: SWBAT describe the molecular nature of DNA Welcome to Quarter 2. Your current grade is an 100%. You now have a second chance and a fresh start. You rarely get second chances in life, so lets make this one count. I have taken into account all of your comments and recommendations to improve the classroom culture. Welcome to second quarter!!!! Do Now: 1.Where have you studied DNA before? 2.What do you know about DNA? 3.Since you now have an understanding of the flow of this course, what is your predicted grade for this quarter? 4.Collect a small piece of tape to tape in your guided notes

DNA stands for: D: Deoxyribose N: Nucleic A: Acid DNA is too small to see, but under a microscope it looks like a twisted up ladder!

Every living thing has DNA. That means that you have something in common with a zebra, a tree, a mushroom and a beetle!!!!

DNA’s function is to replicate so that your cells can grow DNA helps make proteins. Proteins are necessary to carry out various functions in your body.

DNA is a double helix structure This is the backbone This is a nitrogen base Adenine can only go with Thymine This is a weak hydrogen bond

Each nucleotide is made up of a sugar, a phosphate and a base.

DNA is like a fingerprint because everyone’s is a little different! You can tell people apart by their fingerprints……… and their DNA!

How does the nitrogen base structure provide an identifying characteristic to DNA? The sequencing (order) of the bases provides a code (instructions) to make a certain proteins. For example:

Post Lab Questions (to be written in your books) DNA stands for _________________. The DNA is found on the ______ which is found in the nucleus of cells. The backbone of DNA is made up of alternating _______ and _______ groups. The ____ on my model represents the backbone of DNA. The 4 nitrogen bases are ______, ________, __________, and ______. The _______ on my model represents the nitrogen bases. Adenine always pairs with _______. ________ always pairs with _________. The nitrogen bases are held together by a weak _____ bond. The three molecules that make up a nucleotide are _______, ________, and ________.

Exit ticket 1.Name the four bases that pair together DNA? 2.The backbone of DNA is made up of what two molecules? 3.What are the two functions of DNA?

Within cells, DNA is organized into structures called chromosomes. DNA Molecule These chromosomes are duplicated before cells divide, in a process called DNA replication.

The backbone of the DNA strand is made from alternating phosphate and sugar residues. DNA Molecule Genomic DNA is located in the cell nucleus of eukaryotes, as well as small amounts in mitochondria and chloroplasts. In prokaryotes, the DNA is held within an irregularly shaped body in the cytoplasm called the nucleoid.

The genetic information in a genome is held within genes, and the complete set of this information in an organism is called its genotype. DNA Molecule A gene is a unit of heredity and is a region of DNA that influences a particular characteristic in an organism.

Soooo…. How do we tell people apart just by their DNA anyways???

We are ALL a little bit different! Along with the meaningful DNA that encodes for physical traits, we have a lot of "junk DNA." Strings of repeating patterns and filler material. STR stands for short terminal repeating sections, and this area of DNA represents a pattern, 2 to 7 letters long that repeats itself many times. How many times varies between people. This process is called genetic fingerprinting, or more accurately, DNA profiling.

Suspect #1 DNA sample Our DNA has different sizes of pieces so it makes a different pattern when it’s all cut up. Suspect #2 DNA sample In DNA profiling, the lengths of variable sections of repetitive DNA, such as short tandem repeats, are compared between people. This method is usually an extremely reliable technique for identifying a criminal

This is what it really looks like!!! Suspect #1 Suspect #2 Genetic fingerprinting is used in forensic science, to match suspects to samples of blood, hair, saliva or semen.

Can you guess which one is Sara and which one is Miss Ellis? Which suspects DNA sample is the red box around? ? Suspect #1Suspect #2

Now let’s solve a mystery using DNA clues! (Just like they do on CSI!!!)

Miss Maize was returning from a shopping trip to the market, arms filled with groceries when a young man stopped her to ask for directions. She put down her groceries and was helping the man when another person snatched her bags from right beside her. She didn’t see the person’s face but managed to grab hold of his arm for a second and scratched his skin.

Full name: Miss Mary Matilda Maize Age: 26 years old Profession: Professional Sky Diver who knows that the best way to stay fit is to eat lot of vegetables.

Name: Tony Tuber Suspected because: Tony was caught at the local Safeway last year trying to sneak turnips out in his t-shirt.

Name: Randy Raddichio Suspected because: A witness saw Randy chowing down on some radishes just moments after the veggie snatching.

Name: Fanny Fennel Suspected because: Fanny is also a skydiver and the long time enemy of Miss Maize. She would like nothing more than for Miss Maize to not eat her vegetables and not be able to compete as well in the big competition next week.

At each station there will be a question. If you answer the question correctly you will get a DNA clue. At the end, look at the clues and figure out who stole Miss Maize’s vegetables!

1.Presentation about DNA (Time: 15 minutes) 2.Extracting DNA from an onion (Time: minutes) a.May be done as an experiment in front of the class rather than as an activity for everyone to participate in (as you need a blender, use of a knife, etc) 3.Making a DNA molecule with candy (Time: minutes) a)DNA molecule can be made with licorice as the backbone and mini marshmallows of different colours as the bases b)Can the kids have food in class? (Any allergies?) 4.Playing a “CSI-style” mystery game (Time: minutes) a.The class will be broken up into groups of 2-4 children. b.I will present the case, with suspects and the victim of the crime (I won’t choose a violent crime, something like a purse snatching!) c.There will be different stations where groups can get clues if they answer questions right about DNA.