Urry 3rd edition Campbell Biology in Focus Ch 9 The Cell Cycle A v a i l a b l e o n P e a r s o n C h a n n e l s w w w p e a r s o n c o m c h a n n e l s Urry 3rd edition Campbell Biology in Focus Ch 9 The Cell Cycle CONCEPT INTRODUCTION TO CELL DIVISION Cell Division process of a single parent cell dividing or splitting into 2 cells 3 main types of cell division 1 Fission cell division 1 2 eukaryotic cell division producing cells body cells 2 3 3 eukaryotic cell division producing sex cells Human gametes are n since they have copy of every chromosome Human somatic cells are 2n since they have copies of every chromosome EXAMPLE Different Types of Cell Division PRACTICE Which of the following statements about cell division is correct a It is the process by which one parent cell divides into 2 daughter cells b It is an unnecessary process once an organism reaches maturity c It is the process by which two sex cells fuse d It occurs in 2 stages of mitosis then meiosis in all types of cells PRACTICE Which one of the following best defines binary fission a The process by which one cell splits into two cells b The process by which one cell splits into four cells c The process by which two cells combine to create a new cell d The process by which gametes are created Page 1 Urry 3rd edition Campbell Biology in Focus Ch 9 The Cell Cycle Two sources of DNA Genetically offspring Only one source of DNA Genetically offspring 1 Reproduction no sexual activity only parent involved 1 2 2 Reproduction sexual activity parents involved CONCEPT INTRODUCTION TO CELL DIVISION Asexual vs Sexual Reproduction All living organisms must or generate offspring via one of types of reproduction EXAMPLE Asexual vs Sexual Reproduction PRACTICE Asexual reproduction differs from sexual reproduction in that a Asexual reproduction produces genetically diverse offspring b Asexual reproduction occurs only in bacteria c Asexual reproduction produces genetically identical offspring d Asexual reproduction does not occur in animals Importance of Cell Division Cell Division is an important process for reproduction making more life fetal development growth tissue repair Before any cell can divide it must first its DNA so each daughter cell can get a copy of the DNA Page 2 Urry 3rd edition Campbell Biology in Focus Ch 9 The Cell Cycle CONCEPT ORGANIZATION OF DNA IN THE CELL Genome the complete set of of the cell s DNA a Genetic Material molecules that determine the inherited traits of an organism usually a DNA associates with proteins called b to form units called nucleosomes c Nucleosomes units of histone proteins at the core with DNA wrapped around it b c d e d Chromatin packed coiled nucleosomes in non dividing cells e Chromosomes packed highly condensed nucleosomes in a dividing cell Nucleosomes in a cell take different forms depending on if the cell is dividing or EXAMPLE Organization of DNA in the Cell PRACTICE A collection of DNA and associated proteins in a cell defines the term PRACTICE Choose the option that correctly lists the following genetic material in a dividing cell from smallest to largest a Sister Chromatids b Centromere c Chromatin d Chromosome a DNA Chromatin Nucleosomes Chromosomes b Chromatin Nucleosomes Chromosomes DNA c DNA Nucleosomes Chromatin Chromosomes d Chromosomes Chromatin Nucleosomes DNA CONCEPT ORGANIZATION OF DNA IN THE CELL Page 3 Urry 3rd edition Campbell Biology in Focus Ch 9 The Cell Cycle DNA Replication produces an exact of all the DNA in a cell Converts replicated chromosomes replicated chromosomes with identical sister chromatids Chromatid of a replicated chromosome joined to another chromatid at the DNA Replication Produces Replicated Chromosomes Recall Before a cell can divide the DNA must be synthesized duplicated PRACTICE Sister chromatids are a Genetically identical attached by a centromere b Genetically different attached by a centromere c Genetically different attached at the genome d Genetically identical attached at the chromosome PRACTICE The structures labeled Y in the image below are called a Centromeres b Centrioles c Sister chromatids d Spindles Y Page 4 Urry 3rd edition Campbell Biology in Focus Ch 9 The Cell Cycle CONCEPT INTRODUCTION TO THE CELL CYCLE Cell a representation of the events that a cell performs from the moment it is formed to when it divides 1 1 a non dividing phase for cell growth DNA replication production of organelles enzymes Cell cycle is broken down into major phases Includes 4 subphases 2 Mitotic Phase a dividing phase that separates the genetic material while producing multiple cells 2 M Phase Cytokinesis Mitosis consists of phases which we will discuss later 2 EXAMPLE Phases of the Cell Cycle PRACTICE Before a cell divides what must occur 1 a Duplicating the cell s organelles b Replicating the cell s genome c Duplicating enzymes needed for cellular division d All of the above must occur before a cell can divide PRACTICE When cells exit either semi permanently or permanently from the cell cycle and develop a specific function they are said to be in phase a G0 b G1 c G2 d G3 e S Page 5 Urry 3rd edition Campbell Biology in Focus Ch 9 The Cell Cycle A cytoplasmic protein called the centrosome is also replicated in the S phase Makes up majority of the cell cycle interphase take a long time while the M phase is relatively CONCEPT INTERPHASE Recall Interphase is a dividing stage of cell growth organelle enzyme production in preparation for cell division Sub phases of Interphase Interphase is separated into sub phases based on specific events occurring inside the cell 1 1 Growth cell performs its normal functions growing producing organelles enzymes proteins 2 2 Synthesis DNA ynthesis replication producing replicated chromosomes with 2 sister chromatids 3 3 Growth cell continues growth produces new proteins required for phase Sub phase a non dividing phase where cells do replicate their DNA nor prepare for division PRACTICE Cells spend the majority of their time in which one of the following phases of the cell cycle 2 1 3 a Interphase b Prometaphase c Metaphase d Anaphase PRACTICE The first phase in the cell cycle G1 corresponds to a The phase between DNA replication and the M phase b The beginning of mitosis c The phase in which DNA is being replicated d Normal growth and cell function Page 6 Urry 3rd edition Campbell Biology in Focus Ch 9 The Cell Cycle CONCEPT INTERPHASE PRACTICE Which pair includes a phase of the cell cycle and a cellular