The Structure of the DNA Molecule The finger print that is inside your body!

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

DNA is made up of steps and rails of a ladder. This is a rail This is a step Green can only go with Red Purple can only go with Yellow

Deciphering DNA's structure. DNA is made up of subunits which scientists called nucleotides. Each nucleotide is made up of a sugar, a phosphate and a base. There are 4 different bases in a DNA molecule: adenine Cytosine Guanine thymine

Deciphering DNA's structure. 5. The number of adenine bases equals the number of thymine bases because they pair together 6. The number of guanine bases equals the number of cytosine bases because they pair together. 7. The basic structure of the DNA molecule is helical, with the bases being stacked on top of each other

Lets PRACTICE!!

DNA Molecule The Impossibility of Information The DNA molecule is one of the greatest scientific discoveries of all time. First described by James Watson and Francis Crick in 1953, DNA is the famous storehouse of genetics that establishes each organism's physical characteristics.

DNA is like a fingerprint because everyone’s is a little different! You can tell people apart by their fingerprints……… and their DNA! How would the police look at DNA to figure out who committed a crime?

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

DNA Molecule The backbone of the DNA strand is made from alternating phosphate and sugar residues. 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.

DNA Molecule The genetic information in a genome is held within genes, and the complete set of this information in an organism is called its genotype. 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.

Our DNA has different sizes of pieces so it makes a different pattern when it’s all cut up. Suspect #1 DNA sample 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 #2 Suspect #1                                                    Genetic fingerprinting is used in forensic science, to match suspects to samples of blood, hair, saliva or semen. This is what it really looks like!!!

Can you figure it out? Suspect #1 Suspect #2 ? Which suspects DNA sample is the red box around?

Now let’s watch a movie on DNA!