AP Biology Chapter 13 Guided Reading Assignment
1. Compare Compare and contrast contrast asexual asexual and sexual reproductio reproduction. n. in asexual reproduction some individual copies all of its genes to its offspring. whereas in sexual reproduction two individuals produce offspring that have unique combinations of genes from the parent organisms. 2. Defi Define ne the the foll follow owin ing g terms terms:: a. Life cy cycle t is the generation to generation sequence of stages in the reproductive history of an organism! from conception to production of its own offspring. b. "omatic cell #ny cell other than a gamete. c. $aryotype t is the chromosomes when they are arranged in pairs. d. %omol %omolog ogous ous chrom chromos osom omes es t is when two chromosomes composing a pair have the same length! centromere position! and staining pattern. e. "ex "ex chro chrom mosom osomes es &he x and y determine the sex of the individual f. #utosomes #ll the other chromosomes that don't determine sex. g. Dipl Diploi oid d cel cell #ny cell with two chromosome sets. h. %apl %aploi oid d cel cell #ny somatic cells! gamete contain a single chromosome set. i. (er (ertili)at )ation t is the union of gametes! culminating in fusion of their nuclei. *. +ygote t is the fertili)ed egg. ,. meiosis &his type of division reduces the number of sets of chromosomes from two to one in the gametes. -. %ow %ow are ,ary ,aryot otyp ypes es prep prepar ared ed ,aryotypes are produced from isolated somatic cells which are forced to stimulate mitosis over several days /. Describe Describe the the three three diffe different rent types of life life cycles. cycles. animals0in animals gametes are only haploid cells. itosis happens while the p roduction of gametes is occurring then they don't do n't undergo any more division after fertili)ation. &he diploid )ygote divided through the process of mitosis producing a diploid multicellular organism. lants0&he diploid phase is called the sporophyte. eiosis produces spores which are haploid cells. &heses spores divide through the process of mitosis ma,ing a multicellular haploid stage called the gametophyte.
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(ungi0after the gametes fuse together they form a diploid )ygote! meiosis occurs without a diploid offspring developing. eiosis produces haploid cells that divide in mitosis and produce a haploid multicellular adult organism. 3. 4hat exactly is meant by alternation of generations 4ell! it's a life cycle where there are both a multicellular diploid form! called the sporophyte! and a multicellular haploid form! called the gametophyte. 5. Complete the diagram below outlining an overview of meiosis.
6. 4hat are the two broad goals of meiosis &he two goals are to produce haploid daughter cells and generate variation. 7. Label the following diagrams of meiosis.
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8. "ummari)e the comparison of mitosis and meiosis. 9ne large difference between the two is that meiosis reduces the nu mber of chromosomes in the cell produced by half the original amount! but mitosis produces exact copies. &he most important difference is that mitosis produces cells that help with growth and tissue repair whereas meiosis produces only gametes. 1. Describe in detail the three sources of genetic variation in meiosis.
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a. ndependently assorted chromosomes0occurs in metaphase 1. 4hen they are lined up there is an equal chance to receive a chromosome from the father or from the mother. b. ;enetic recombination or commonly ,nown as crossover0occurs in prophase 1! this occurs when the chromatids of both homologous chromosome pairs bring their arms together and attach by a protein structure called the synaptonemal complex. &hen a non0sister chromatid pair crosses its genes with its neighbor. &his effectively changes the codons in that gene and those of the daughter cell that will receive that chromatid. &his also increases the variety of potential gametes produced in mitosis. c.
other members of species=favorable traits win out=Darwinism.
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