DNA Deoxyribonucleic Acid “living code”

DNA The genetic material of a cell contains information for the cell’s growth and other activities.

DNA DNA - is an organic compound called deoxyribonucleic acid. It is the cell’s genetic material. It is the instructions for life. vocabulary word!

What does DNA look like? The shape of DNA is a twisted ladder shape called a double helix. The “sides” of the ladder are made from sugars and phosphate groups. The “rungs” of the ladder are made of amino acid base pairs.

DNA nucleotide – the bases that DNA is made up of –adenine (A) –guanine (G) –cytosine (C) –thymine (T) vocabulary word!

Just like a puzzle, certain bases MUST fit together. guanine (G) always pairs with cytosine (C) thymine (T) always pairs with adenine (A) A G T C C A G T A A TCAG GT CA TT

The order of these nucleotides in DNA is the code for the organism. Each individual has a unique “code”.

Copying DNA during Mitosis Think way back to our unit on mitosis. Remember, the DNA in the nucleus must be copied before the cell can divide. replication – process in which the cell makes a copy of its DNA. vocabulary word!

Replication 1.The two strands of DNA separate or “open” 2.The bases on each side are used as a pattern. 3.Complementary bases are added to each side. 4.Two strands are created. Each one has an “old” side and a new side.

Replication y8fNkCw

Mutations During Replication Sometimes, mistakes occur during replication. mutation – changes in the number, type or order of bases on a piece of DNA. –deletion – a base or bases are left out –insertion – a base or bases are added –substitution – a base or bases is changed vocabulary word!

Some mutations can be fixed Mutations can be beneficial, neutral or harmful depending on what they are.

Genetic Mutations Gene undergoes a change An error in the copying of the DNA Some mutation are beneficial Some mutation are harmful

1jtUQhttps:// 1jtUQ