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MEIOSIS 11-4. http://waynesword.palomar.edu/lmexer2a.htm. Making gametes…. Remember from Chapter 1: CHARACTERISTICS OF LIVING THINGS ALL LIVING THINGS __________. Planaria animation: http://www.t3.rim.or.jp/~hylas/planaria/title.htm Family http://babyhearing.org/Parenet2Parent/index.asp.
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MEIOSIS11-4 http://waynesword.palomar.edu/lmexer2a.htm Making gametes…
Remember from Chapter 1:CHARACTERISTICS OF LIVING THINGSALL LIVING THINGS __________ Planaria animation: http://www.t3.rim.or.jp/~hylas/planaria/title.htmFamily http://babyhearing.org/Parenet2Parent/index.asp
ASEXUAL REPRODUCTION http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookmito.html Bacteria reproduce using __________________________________ Budding & regeneration are used by plants and animals to reproduce asexually (mitosis) http://fig.cox.miami.edu/~cmallery/150/mitosis/c7.13.2.hydra.jpg Planaria animation: http://www.t3.rim.or.jp/~hylas/planaria/title.htm
MITOSIS Produces cells that are __________ copies of parent cell
ADVANTAGES OF ASEXUAL REPRODUCTION Can make offspring faster Don’t need a partner http://www.mrgrow.com/images/cutting.jpg
DISVANTAGES OF ASEXUAL REPRODUCTION ALL ALIKE Species CAN’T change and adapt One disease can wipe out whole population http://www.mrgrow.com/images/cutting.jpg
SEXUAL REPRODUCTION Family image from: http://babyhearing.org/Parenet2Parent/index.asp Combines genetic material from 2 parents (sperm & egg) so offspring are genetically __________ from parents
ADVANTAGES OF SEXUAL REPRODUCTION Allows for variation in population Individuals can be different Provides foundation for EVOLUTION Allow species adapt to changes in their environment http://naturalsciences.sdsu.edu/classes/lab8/spindex.html
http://www.angelbabygifts.com/ Image by Riedell Image by Riedell EGG + SPERM If egg and sperm had same number of chromosomes as other body cells . . . baby would have too many chromosomes! http://www.acmecompany.com/stock_thumbnails/13217.forty-six_chromosomes.jpg
MEIOSIS is the way… to make cells with ½ the number of chromosomes for sexual reproduction http://waynesword.palomar.edu/lmexer2a.htm
Video 1 Video 1 Meiosis Overview Click the image to play the video segment 11A.
DIPLOID & HAPLOID Most cells have 2 copies of each chromosome = ______________ (one from mom; one from dad) All BODY (___________) cells are diploid HOMOLOGOUSCHROMOSOMES
DIPLOID & HAPLOID Some cells have only one copy of each chromosome = _____________ All sperm and egg cells are haploid
MITOSIS • Makes ___ cells genetically _________ to parent cell & to each other • Makes ___ cells • Makes __________ • Used by organisms to: increase size of organism, repair injuries, replace worn out cells http://waynesword.palomar.edu/lmexer2a.htm
MEIOSIS • Makes ____ cells genetically different from parent cell & from each other • Makes _____ cells • Makes ______________ • Used for ____________ http://waynesword.palomar.edu/lmexer2a.htm
WHAT MAKES MEIOSIS DIFFERENT ? • SYNAPSIS & CROSSING OVER (PROPHASE I) • SEGREGATION & INDEPENDENT ASSORTMENT (ANAPHASE I) 3. Skip INTERPHASE II (NO S) CELL DIVIDES TWICE, BUT… ONLY COPIES DNA ONCE
WHAT MAKES MEIOSIS DIFFERENT ? • Homologous chromosomes pair up during ____________= ______________ This group of FOUR (4) chromatids is called a _________________ Images modified from: http://www.emc.maricopa.edu/faculty/farabee/BIOBK/Crossover.gif
WHAT MAKES MEIOSIS DIFFERENT? 1. Exchange of DNA betweenhomologous pairs = _____________during PROPHASE I Allows shuffling of genetic material http://www.emc.maricopa.edu/faculty/farabee/BIOBK/Crossover.gif
Video 5 Video 5 Crossing Over • Click the image to play the video segment. 11E SEE CROSSING OVERANIMATION
HOMOLOGOUS CHROMOSOMES Image modified by Riedell • SAME SIZE • SAME SHAPE • CARRY GENES for the SAME TRAITS • BUT ______________! (Don’t have to have the SAME CHOICES) http://sps.k12.ar.us/massengale/genetics%20tutorial.htm
Image modified by Riedell CROSSING OVER • Allows for_________________ in different combinations • After crossing over, chromatid arms are________________ anymore http://sps.k12.ar.us/massengale/genetics%20tutorial.htm
WHAT MAKES MEIOSIS DIFFERENT ? 2.Separation during ANAPHASE I __________________ & _______________________ Separates gene choices and allows shuffling of genetic material
Video 4 Video 4 Segregation of Chromosomes Click the image to play the video segment 11D.
SEGREGATION & CROSSING OVERtogether make even more combinations See ananimation http://waynesword.palomar.edu/lmexer2a.htm
INDEPENDENT ASSORTMENT http://fig.cox.miami.edu/~cmallery/150/mitosis/c13x9independent-assortment.jpg
INDEPENDENT ASSORTMENTat ANAPHASE I Lots of different combinations are possible! This is why you don’t look exactly like your brothers and sisters even though you share the same parents!
WHAT MAKES MEIOSIS DIFFERENT ? Crossing over Segregation Independent assortment are ALL ways MEIOSIS results in =______________________________ So daughter cells are ______________ from parents and from each other
WHAT MAKES MEIOSIS DIFFERENT ? 3. Skip INTERPHASE II (No S) CELL DIVIDES TWICE, BUT … ONLY COPIES ITS DNA ONCE MITOSIS: P M A C G1 T S G2 MEIOSIS: ( I ) G1 A T C S G2 P M ( II ) A P M T C
Video 2 Video 2 Animal Cell Meiosis, Part 1 & Part 2 Click the image to play the video segment 11B. & C
Figure 11-15 Meiosis Section 11-4 Meiosis I
Figure 11-17 Meiosis II Section 11-4 Meiosis II Prophase II Metaphase II Anaphase II Telophase II Meiosis I results in two haploid (N) daughter cells, each with half the number of chromosomes as the original. The chromosomes line up in a similar way to the metaphase stage of mitosis. The sister chromatids separate and move toward opposite ends of the cell. Meiosis II results in four haploid (N) daughter cells.
MITOSIS vs MEIOSISINTERPHASE INTERPHASE I http://www.pbs.org/wgbh/nova/baby/divi_flash.html • DNA is spread out as chromatin • Nuclear membrane/ nucleolus visible • DNA is copied during S phase • Makes stuff new cell needs in G2 _______________
MITOSIS vs MEIOSIS PROPHASE PROPHASE I http://www.pbs.org/wgbh/nova/baby/divi_flash.html DNA scrunches into chromosomes Nuclear membrane/ nucleolus disappear Centrioles/spindle fibers appear DNA scrunches into chromosomesNuclear membrane/ nucleolus disappear Centrioles/spindle fibers appear _________________________
MITOSIS vs MEIOSIS METAPHASE METAPHASE I http://www.pbs.org/wgbh/nova/baby/divi_flash.html • Chromosomes line up in middle Chromosomes line up in middle ______________________________
MITOSIS vs MEIOSIS ANAPHASE ANAPHASE I http://www.pbs.org/wgbh/nova/baby/divi_flash.html APART: Chromatids split APART: Chromatids stay together________________________
MITOSIS vs MEIOSIS TELOPHASE TELOPHASE I http://www.pbs.org/wgbh/nova/baby/divi_flash.html See TWO nuclei Nuclear membrane/ nucleolus return DNA spreads out as chromatin Spindle/centrioles disappear ____________________
MITOSIS vs MEIOSIS CYTOKINESIS CYTOKINESIS I http://www.pbs.org/wgbh/nova/baby/divi_flash.html Cytoplasm splits into 2 cells ______________________
MITOSIS vs MEIOSIS INTERPHASE II http://www.pbs.org/wgbh/nova/baby/divi_flash.html • DNA is spread out as chromatin • Nuclear membrane/ nucleolus visible • DNA is copied during S phase ______________________________________________________
MITOSIS vs MEIOSIS PROPHASE PROPHASE II http://www.pbs.org/wgbh/nova/baby/divi_flash.html • DNA scrunches into chromosomes • Nuclear membrane/nucleolus disappear • Centrioles/ spindle fibers appear ____________________
MITOSIS vs MEIOSIS METAPHASE METAPHASE II http://www.pbs.org/wgbh/nova/baby/divi_flash.html • Chromosomes line up in middle ______________________
MITOSIS vs MEIOSIS ANAPHASE ANAPHASE II http://www.pbs.org/wgbh/nova/baby/divi_flash.html Chromatids split and move apart __________________________
MITOSIS vs MEIOSIS TELOPHASE TELOPHASE II http://www.pbs.org/wgbh/nova/baby/divi_flash.html Two nuclei Nuclear membrane/nucleolus returns Centrioles/spindle fibersdisappear DNA spreads out as chromatin _______________________
MITOSIS vs MEIOSIS CYTOKINESIS CYTOKINESIS II http://www.pbs.org/wgbh/nova/baby/divi_flash.html Cytoplasm splits _____________________ http://www.pbs.org/wgbh/nova/baby/divi_flash.html
Ways Meiosis is different? • Homologous pairs match up & trade DNA (SYNAPSIS & CROSSING OVER) in PROPHASE I • SEGREGATION • &INDEPENDENT ASSORTMENT in Anaphase I • create genetic recombination • Skipping INTERPHASE II- • (Dividing TWICE but copying DNA once) • produces 1n cells
___________________= MAKING MATURE SPERM Mature & grow flagella
Sperm provides DNA All the starting nutrients, organelles, molecule building blocks, etc. have to come from the egg.
__________________ = MAKING a MATURE EGG Produces: 1 “good” egg 3 __________ CYTOPLASM DIVIDES UNEVENLY