End Show Slide 1 of 21 Copyright Pearson Prentice Hall 12-2 Chromosomes and DNA Replication 12–1&2 Chromosomes and DNA

End Show 12–2 Chromosomes and DNA Replication Slide 2 of 21 Vocabulary words Copyright Pearson Prentice Hall DNA Nucleotide Purine Pyramidine Chargaff's Rules Double Helix Hydrogen Bonds Histone Nucleosome Chromosome Gene

End Show 12–2 Chromosomes and DNA Replication Slide 3 of 21 Outline –DNA structure Chargaff’s rule –Chromosomes Structure Pairing Copyright Pearson Prentice Hall

End Show 12–2 Chromosomes and DNA Replication Slide 4 of 21 Deoxyribonucleic acid (DNA) - a molecule that encodes the genetic instructions used in all living organisms and many viruses. Gene – single unit of heredity Copyright Pearson Prentice Hall

End Show 12–2 Chromosomes and DNA Replication Slide 5 of 21 Copyright Pearson Prentice Hall The Components and Structure of DNA There are four kinds of bases in in DNA: adenine guanine cytosine thymine

End Show 12–2 Chromosomes and DNA Replication Slide 6 of 21 Copyright Pearson Prentice Hall The Components and Structure of DNA Chargaff's Rules Erwin Chargaff discovered that: The percentages of guanine [G] and cytosine [C] bases are almost equal in any sample of DNA. The percentages of adenine [A] and thymine [T] bases are almost equal in any sample of DNA.

End Show 12–2 Chromosomes and DNA Replication Slide 7 of 21 Copyright Pearson Prentice Hall The Components and Structure of DNA DNA Double Helix

End Show 12–2 Chromosomes and DNA Replication Slide 8 of 21 Copyright Pearson Prentice Hall DNA and Chromosomes In prokaryotic cells, DNA is located in the cytoplasm. Most prokaryotes have a single DNA molecule containing nearly all of the cell’s genetic information.

End Show 12–2 Chromosomes and DNA Replication Slide 9 of 21 Copyright Pearson Prentice Hall DNA and Chromosomes Eukaryotic DNA is located in the cell nucleus inside chromosomes. Many eukaryotes have 1000 times the amount of DNA as prokaryotes.

End Show 12–2 Chromosomes and DNA Replication Slide 10 of 21 Nucleus – Control center of the cell. Contains DNA Copyright Pearson Prentice Hall

End Show 12–2 Chromosomes and DNA Replication Slide 11 of 21 Nucleus Envelope - double lipid bilayer which surrounds the DNA and nucleolus Chromatin - the combination of DNA and proteins that make up the contents of the nucleus of a cell. (makes chromosomes) Nucleolus – dark dense center of the nucleus. Where ribosome are made Copyright Pearson Prentice Hall

End Show 12–2 Chromosomes and DNA Replication Slide 12 of 21 Copyright Pearson Prentice Hall DNA and Chromosomes Chromosome Structure Both Prokaryotes and Eukaryotes have the same structure of DNA Eukaryotic cells contain chromosomes which are molecules that contain DNA and protein, tightly packed together..

End Show 12–2 Chromosomes and DNA Replication Slide 13 of 21 Chromosome - is an organized structure of DNA, protein, found in cells. It is a single piece of coiled DNA containing many genes.. Centromere – center of chromosome Chromatid - is one copy of a duplicated chromosome Copyright Pearson Prentice Hall

End Show 12–2 Chromosomes and DNA Replication Slide 14 of 21 Copyright Pearson Prentice Hall DNA and Chromosomes Eukaryotic Chromosome Structure Chromosome Supercoils Nucleosome DNA double helix Histones Coils

End Show 12–2 Chromosomes and DNA Replication Slide 15 of 21 Histone – Protein that packages and orders DNA into structural units called nucleosomes Nucleosome - DNA wound around histone protein cores Copyright Pearson Prentice Hall

End Show 12–2 Chromosomes and DNA Replication Slide 16 of 21 Copyright Pearson Prentice Hall DNA and Chromosomes Eukaryotic Chromosome Structure Chromosome Supercoils Nucleosome DNA double helix Histones Coils

End Show 12–2 Chromosomes and DNA Replication Slide 17 of 21 Humans have 46 pairs of chromosomes –23 from your mom –23 from your dad Last 2 chromosomes pairs determine sex of child –XX Girl –XY Boy The number of chromosomes varies from one species to the next. Copyright Pearson Prentice Hall

End Show - or - Continue to: Click to Launch: Slide 18 of 21 Copyright Pearson Prentice Hall 12–2

End Show Slide 19 of 21 Copyright Pearson Prentice Hall 12–2 In prokaryotic cells, DNA is found in the a.cytoplasm. b.nucleus. c.ribosome. d.cell membrane.

End Show Slide 20 of 21 Copyright Pearson Prentice Hall 12–2 A DNA molecule separates, and the sequence GCGAATTCG occurs in one strand. What is the base sequence on the other strand? a.GCGAATTCG b.CGCTTAAGC c.TATCCGGAT d.GATGGCCAG

End Show Slide 21 of 21 Copyright Pearson Prentice Hall

End Show Slide 22 of 21 Copyright Pearson Prentice Hall

End Show Slide 23 of 21 Copyright Pearson Prentice Hall 12–2

End Show Slide 24 of 21 Next class Homework: Glue QR codes to notes and watch the video on the on the QR code for next class (the cell cycle). Possible quiz on vocabulary next class –matching Copyright Pearson Prentice Hall

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