Power Point Presentation to Accompany 2010 Delmar Cengage

Power. Point Presentation to Accompany © 2010 Delmar, Cengage Learning

Chapter 4 Cellular Metabolism and Reproduction: Mitosis and Meiosis © 2010 Delmar, Cengage Learning 2

Introduction to Cellular Metabolism • Metabolism: total cellular chemical changes – Anabolism: process of building up – Catabolism: process of breaking down • Calorie: measure of energy contained in food • ATP: energy source available to the cell © 2010 Delmar, Cengage Learning 3

Cellular Metabolism or Biochemical Respiration © 2010 Delmar, Cengage Learning 4

Glycolysis • Breakdown of glucose • Anaerobic or aerobic process • Final outcome – 2 pyruvic acid molecules, 2 ATP molecules (anaerobic), 8 ATP molecules (aerobic) © 2010 Delmar, Cengage Learning 5

The Krebs Citric Acid Cycle • Pyruvic Acid > Acetyl-Co. A • Acetyl-Co. A enters Krebs cycle in mitochondria • Final outcome – 6 CO 2, 8 NADH 2, 2 FADH 2, 2 ATP (GTP) © 2010 Delmar, Cengage Learning 6

The Electron Transport (Transfer) System • • Series of reduction/oxidation reactions Requires O 2 Electron carriers Number of ATP molecules dependent on electron carrier • Water is a waste product © 2010 Delmar, Cengage Learning 7

Summary of ATP Production • During glycolysis, the citric acid cycle, and electron transport • Glycolysis: 8 ATP (aerobic) • Krebs cycle and electron transport – 28 ATP + 2 GTP or – 30 ATP • 1 glucose molecule yields 38 ATP © 2010 Delmar, Cengage Learning 8

Anaerobic Respiration © 2010 Delmar, Cengage Learning 9

Fermentation • Yeast breaks down glucose anaerobically • Pyruvic acid broken down by decarboxylase – Forms carbon dioxide and acetaldehyde • Final products: 2 ATP, CO 2, ethyl alcohol © 2010 Delmar, Cengage Learning 10

Anaerobic Production of ATP by Muscles • Pyruvic acid converted to lactic acid – Accumulation of lactic acid causes fatigue in muscles – When oxygen supplied, lactic acid turns back into pyruvic acid • 2 ATP produced per glucose molecule © 2010 Delmar, Cengage Learning 11

Production of ATP from General Food Compounds © 2010 Delmar, Cengage Learning 12

Production of ATP from General Food Compounds (cont’d. ) • Carbohydrates fit into cellular furnace at same level as glucose – Can be stored in liver or as fat • Fats digested into fatty acids and glycerol – Glycerol enters at PGA stage of glycolysis – Fatty acids enter Krebs citric acid cycle © 2010 Delmar, Cengage Learning 13

Production of ATP from General Food Compounds (cont’d. ) • Proteins digested into amino acids – Enter into Krebs cycle at different stages • Dependent on chemical structure © 2010 Delmar, Cengage Learning 14

Introduction to Cellular Reproduction © 2010 Delmar, Cengage Learning 15

Introduction to Cellular Reproduction (cont’d. ) • • Process of cell duplication Mitosis: duplication of genetic material Cytokinesis: duplication of organelles Meiosis: reduction division only in gonads © 2010 Delmar, Cengage Learning 16

The Structure of the DNA Molecule © 2010 Delmar, Cengage Learning 17

The History of the Discovery of DNA • • Friedrich Miescher, 1869: first discovery P. A. Levine, 1920 s: composition Rosalind Franklin: helical structure Watson and Crick: three-dimensional structure © 2010 Delmar, Cengage Learning 18

The Anatomy of the DNA Molecule • Double helical chain of nucleotides – Phosphate group – Five-carbon sugars (deoxyribose) – Nitrogen-containing base • Pyrimidines (thymine and cytosine) • Purines (adenine and guanine) – Pyrimidines pair with purines – Chains held together by hydrogen bonds © 2010 Delmar, Cengage Learning 19

The Anatomy of the DNA Molecule (cont’d. ) • Gene: sequence of base pairs that codes for polypeptide or protein • Human Genome Project – 3 billion base pairs that code for 30, 000 genes • Duplication of DNA molecule – Helicase separates at hydrogen bonds – DNA polymerase adds new nucleotides © 2010 Delmar, Cengage Learning 20

The Cell Cycle © 2010 Delmar, Cengage Learning 21

Introduction • All reproduction begins at cellular level • Interphase – Previously called resting stage • Mitosis • Cytokinesis © 2010 Delmar, Cengage Learning 22

Interphase • Time between divisions – G 1: Primary growth phase – S: DNA duplication – G 2: Centrioles complete duplication, mitochondria replicate, chromosomes condense and coil © 2010 Delmar, Cengage Learning 23

Mitosis • Prophase – Chromosomes become visible as chromatids joined by centromere – Two kinetochores at the centromere – Centrioles move to opposite poles – Nuclear membrane breaks down – Microtubules attach kinetochores to spindle © 2010 Delmar, Cengage Learning 24

Mitosis (cont’d. ) • Metaphase – Chromatids align at equator of cell – Centromere divides © 2010 Delmar, Cengage Learning 25

Mitosis (cont’d. ) • Anaphase – Divided centromere pulls chromatids to opposite pole – Cytokinesis begins © 2010 Delmar, Cengage Learning 26

Mitosis (cont’d. ) • Telophase – Chromosomes uncoil and decondense – Spindle apparatus breaks down – New nuclear membrane forms – Cytokinesis nearly complete © 2010 Delmar, Cengage Learning 27

Animation - Mitosis • Stop and watch a 3 -D presentation of mitosis. [Insert mitosis. swf] © 2010 Delmar, Cengage Learning 28

Cytokinesis • Animal cells – Cleavage furrow forms – Cell is pinched into daughter cells • Plant cells – Cell plate forms at equator – Cell plate becomes new cell wall © 2010 Delmar, Cengage Learning 29

Meiosis: A Reduction Division © 2010 Delmar, Cengage Learning 30

Introduction • Occurs only in the gonads • Reduces genetic material from diploid to haploid • Two divisions resulting in four cells © 2010 Delmar, Cengage Learning 31

Stages of Meiosis • Prophase I: homologous chromosomes pair and cross over • Metaphase I: chromosomes align along equator • Anaphase I: centromeres pulled to poles – One member to each pole • Telophase I: one of each pair is at each pole © 2010 Delmar, Cengage Learning 32

Stages of Meiosis (cont’d. ) • Prophase II: spindle forms; centrioles move to poles • Metaphase II: chromosomes line up at equator • Anaphase II: centromeres divide • Telophase II: chromatids at each pole; new nuclear membrane forms © 2010 Delmar, Cengage Learning 33

Animation - Meiosis • Now that you have learned about the stages of meiosis, watch the meiosis animation for a visual of this process. • [Insert meiosis. swf] © 2010 Delmar, Cengage Learning 34

Gametogenesis: The Formation of the Sex Cells © 2010 Delmar, Cengage Learning 35

Gametogenesis: The Formation of the Sex Cells (cont’d. ) • Spermatogenesis – Four cells produced – Develop into sperm • Oogenesis – Four cells produced – Only one becomes functional egg © 2010 Delmar, Cengage Learning 36

Animation – Cancer Metastasizing • Refer to the Common Disease, Disorder or Condition box on Cancer in your textbook and read about the growth of cancer cells. Now watch the 3 -D Cancer Metastasizing animation. • [Insert cancer metastasizing. swf] © 2010 Delmar, Cengage Learning 37

Summary • Discussed how glucose is converted into ATP in the presence of oxygen • Discussed how glucose is converted into ATP in the absence of oxygen • Described how fats and proteins are converted into ATP • Discussed the cell cycle © 2010 Delmar, Cengage Learning 38