DNA Replication and Mutation RED COPY INTO NOTEBOOK
DNA: Replication and Mutation
RED => COPY INTO NOTEBOOK What is DNA? l l l DNA = deoxyribonucleic acid DNA is the “blueprint” for the cell contains the instructions that tells the cell how to do things and what to make DNA is like blueprints for making a city, which in this case is the cell Amoeba Cell
What is DNA made of? l DNA is made up of 4 bases: – Adenine (A), Thymine (T), Cytosine (C), Guanine (G) Rules for DNA Bases: 1. A pairs with T 2. G pairs with C “Chargaff’s Rules”
Structure of DNA l l l DNA is made up of two strands (double stranded) Each strand has the bases connected to a PHOSPHATE BACKBONE The two strands wrap around each other in a winding staircase manner (helix)
Models of DNA
ACTUAL Pictures of DNA
DNA Replication l l In order for you to survive, your cells need to replicate themselves. In order for them to do that, they need to replicate their DNA Every cell in your body has the same DNA, because every time one of your cells divides, it makes a copy of its DNA to give to the new daughter cells
How does DNA replicate? l The DNA is unzipped and the original strands are used to help make the new molecules – See Demonstration
What are mutations? l MUTATIONS are any changes in the sequence of bases of DNA ll. Mutations DO COULD NOT lead to to this Colon cancer cells
How do mutations occur? l l l Sometimes during replication, the cell makes a mistake and adds the wrong base When the cell replicates its DNA again, the two strands that are produced are no longer exactly the same This usually will cause the new cell to die, but sometimes it can cause the cell to divide when it is not supposed to cancer
How do mutations occur? Replication
What can cause mutations to happen more often?
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