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Chapter 4, Section 2 delves into the fascinating world of DNA, highlighting that humans have around 100,000 genes and approximately 30,000 base pairs within each gene, resulting in a staggering total of around 3 billion bases across all genes. It explores the process of protein synthesis where DNA is copied, moves to the cytoplasm, and is translated into proteins via ribosomes with the help of amino acids. It also discusses mutations—changes in the DNA sequence that can occur through deletion, insertion, or substitution—as well as the body's mechanisms to repair DNA and the factors that can cause mutations.
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How DNA Works Chapter 4, Sec. 2
Humans have about 100,000 genes • There are about 30,000 bases in each gene!!
How many bases would be in all your genes? • 3,000,000,000
The DNA code is read 3 bases at a time • The 3 bases code for an amino acid
The amino acids join to form a protein • Humans have about 50,000 different proteins
Ribosomes • Part of the cell where proteins are made
Amino Acids • Make up proteins • 22 known amino acids • Essential (from diet) • Non-essential (body)
Steps for making a protein (pg 89) • Copy DNA strand • DNA moves to cytoplasm • DNA fed through a ribosome • Transfer molecules bring amino acids • Amino acids form a protein
CGT AminoAcids
Mutations • Change in the order of bases • Damage to bases
3 types of mutations: t • Deletion – bases are left ou • Insertion – bases are added • Substitution – bases are replaced (most commun) d
Mutagen • Anything that causes a mutation in DNA • Chemicals, U.V light, X-rays
ATCCGTACT • TAGGCATGA
THE IGR EDC ATA TET HEB IGB ADR AT • THE BIG RED CAT ATE THE BIG BAD RAT