Questions to Consider What changes were critical in getting your cell to divide successfully? What happens to the organelles in the cytoplasm during cell division?

CHAPTER 5 CHROMOSOMES AND CELL REPRODUCTION

About 2 trillion cells are produced by you every day How many/second? About 25 million Egg/Sperm  “Zygote” Embryo  Fetus  Baby

THE CELL CYCLE = sequence of growth and division - Interphase - Mitosis 2 Stages?

G1

S DNA Replication Exact copies of Chromosomes **DNA must be copied then distributed

DNA Gene = a segment of DNA that codes for a protein Gene Genes  You

Gene Chromosome DNA Chromosome = consists of DNA tightly coiled around proteins

Single? 46 # Pairs? 23 “Somatic cells” (body cells) HUMANS

Why pairs? Diploid = 2n Mom Dad Pair 1-22 = Autosomes Pair 23 = Sex Gene   Gene Gene   Gene Pair 1-22 = Autosomes Gene   Gene Gene   Gene Pair 23 = Sex Chromosomes

Human 46 single Molecules that aid? G1? End of S? 46 double Enzymes

G2 Growth/Prep for Mitosis “Centrioles” “Centrioles”

MITOSIS Cytokinesis Acronym? PMAT Phases? Prophase Metaphase Anaphase Telophase Cytokinesis

PMAT 46 46 Cytokinesis 46 46 92 sister chromatids 46 double chromosomes PMAT 46 46 Cytokinesis 46 46

DNA pairs find “partner” Chromosome  DNA pairs find “partner” Sister Chromatids  Replicated Chromosome “Homologous Chromosomes”

M P Pairs? 46 T A  

YouTube - Mitosis

CYTOKINESIS Animal Plant “Cleavage Furrow” “Cell Plate”

Daughter Cells go? Interphase

3 1 Prophase Anaphase 4 Which? Telophase 2 Metaphase 5 Interphase

Control of the Cell Cycle 90% time in Interphase Feedback signals – “red/green light” Controlled by proteins

Cancer = uncontrolled growth/division of cells If gene that contains info for cell growth/division is mutated = Cell growth/division unregulated

Tumor “benign tumor” “malignant tumor” Metastasis Therapy? = a mass of abnormal cells. “benign tumor” “malignant tumor” Metastasis (start more tumors) Therapy? Radiation therapy Chemotherapy with toxic drugs. Mammograms 

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