DNA Deoxyribose Nucleic Acid say: dee-ox-EAR-i-bose new-CLAY-ik A-sid (Genetic Material)

What is DNA? DNA is the genetic material of all living things on the planet. It is found in the nucleus of your cells. DNA holds the instructions to make all things in your body work properly.

Where is DNA found? DNA is found in the nucleus of all plant and animal cells. It is wound up in tight chromosomes.

What does DNA look like? Shape of a double helix or a twisted ladder. The steps of the ladder are called “base pairs” The bases: Adenine (A) say: A-da-nine Guanine (G) say: GWAY-nine Thymine (T) say: THIGH-min Cytosine (C) say: SITE-oh-seen

Base Pairs Each of the bases have a partner they pair off with. Adenine (A) always partners with Thymine (T) Cytosine (C) always partners with Guanine (G) A T C G G C T A G C

Complementary Strand What is the complementary strand for the following sequence? A A T G T C A T G C T A C G G A C T T A C A G T A C G A T G C C T G

Mistakes Happen If the wrong bases pair off with one another it’s called a mutation. Most mutations are harmless. Some can be serious. A T C G G A T C G C

DNA Replication This is when DNA makes a copy of itself. Usually when the cell divides, a copy of the instructions (DNA) is given to the new cell.

How does DNA control the cell? A cell’s DNA needs to change forms. DNA cannot leave the nucleus to give commands, so it needs to make a smaller copy of itself called RNA. RNA leaves the nucleus and is read by the ribosome. say: RYE-boh-sohm The ribosome then makes a protein. The protein is DNA’s command.

Making RNA DNA DNA Unwinds RNA RNA is made RNA has DNA’s instructions and can leave the nucleus

Changing DNA to RNA Transcription To figure out the RNA sequence, base pairs still need to match up. A with T, C with G (for DNA) In RNA the rules still apply, but anywhere a T should be, it is replaced by Uracil (U). say: YUR-uh-sill

What is the RNA sequence? DNA RNA T A A U T A C G G C T A G C A U

What is a gene? A gene is a section of DNA that has instructions for a particular trait. Some genes are dominant (stronger) Some genes are recessive (weaker) Each organism inherits a gene from each parent. Each organism has 2 genes per trait.

Inheritance In the example, each flower has a trait for color: red or yellow. The offspring inherited a red gene from one parent and a yellow gene from the other parent. Red was the expressed color, so it is considered dominant.

Where did the color come from? There was a section of DNA which had the information for color. The RNA form is made and read into a protein that expresses the color. DNA RNA Protein Expressed color

References http://www.pitt.edu/~hpsdept/images/double_helix.gif, Access Date: Dec. 12, 2006 http://www.bst.ntu.edu.tw/images/double%20helix%20c.jpg, Access Date: Dec. 12, 2006 http://www.chemsoc.org/ExemplarChem/entries/2003/imperial_Burgoine/origins.txt.html, Access Date: Dec. 12, 2006 http://library.tedankara.k12.tr/chemistry/vol1/biochem/trans98.jpg, Access Date: Dec. 12, 2006 http://biology.unm.edu/ccouncil/Biology_124/Images/transcription.gif, Access Date: Dec. 13, 2006