Presentation on theme: "What do you already know? Here are some questions to guide you: What does “replication” mean? What are the building blocks of nucleic acids? Where in."— Presentation transcript:
What do you already know? Here are some questions to guide you: What does “replication” mean? What are the building blocks of nucleic acids? Where in the cell is DNA located? What is the function of DNA? DNA Replication
Did You Know… Chromosomes are made of DNA Humans have 46 chromosomes One chromosome can have as little as 50 million base pairs or as much as 250 million base pairs. There’s an estimated 3 billion DNA bases in our genome. If all the DNA in your body was put end to end, it would reach to the sun and back over 600 times !
Did You Know… DNA contains the genes – directions for making proteins Chimps share 98% of their genes with humans Over 99% of our DNA sequence is the same as other humans’.
Vocabulary DNA replication Nucleus Double helix Nucleotide Nitrogen bases Phosphate and Sugar Mutation DNA copies itself Holds DNA 2 strands of DNA twisted together Building blocks of DNA A, T, C, G Make up the “backbone” Mistakes in replication
What is DNA? DNA is a molecule that contains all of the instructions for making new cells or organisms Stored in the nucleus (Eukaryotes only) Gene – segment of DNA that codes for a protein or RNA
What is DNA made of? DNA is made up of nucleotides Nucleotides are made up of 3 parts: Sugar: deoxyribose Phosphate Nitrogen base: adenine (A), thymine (T), guanine (G) and cytosine (C)
What does DNA look like? Double helix shape Two strands twisted around each other If you unwrap all the DNA you have in all your cells, you could reach the moon 6000 times!
Base Pairing Adenine (A) ALWAYS pairs with Thymine (T) Cytosine (C) ALWAYS pairs with Guanine (G)
Stop and Think A scientist determines the percentages of each base in a molecule of DNA. The scientist discovers that 15% of the bases are adenine (A). What are the percentages of the other bases in this DNA molecule? Thymine (T) Cytosine (C) Guanine (G) 15% 35%
DNA Replication (A.K.A. DNA Synthesis ) DNA replication is the process of making a DNA copy that is identical to the original DNA molecule. All cells need to make new DNA in order to make new cells
DNA Replication Original DNA strand DNA strand unwinds and unzips (Enzyme Helicase) Bases match up (Enzyme DNA Polymerase) 2 identical DNA strands