1.         Cell Division

2.         Definitions

            a.         Chromosome: cell structure carrying genes

            b.         Histone: protein controlling coiling of DNA

            c.         Gamete: cells formed during meiosis

            d.         Zygote: cell produced by the union of gametes

3.         Definitions

            a.         Gene: portion of DNA coding for proteins

            b.         Sex Chromosomes: those that determine the sex of organism

            c.         Autosome: those chromosomes that do not determine sex

4.         Chromosome Structure

            a.         Normal Cell

                        i.         Chromatin

                                    (1)       Uncoiled DNA

                                    (2)       Proteins

5.         Chromosome Sturcture

            a.         Dividing Cell (pg 145)

                        i.         DNA replicates

                        ii.        Forms nucleosome

                                    (1)       146 nucleotide group

                                    (2)       Around 8 histones

                                    (3)       Histone tails hold nucleosomes

                        iii.       Linker DNA pulls nucleosomes together

                        iv.       Stacks of nucleosome appear as rods (chromatids)

6.         Chromosome Structure

            a.         Chromosomes

                        i.         2 identical chromatids

                        ii.        Telomeres cap ends of chromatids

                        iii.       Joined at centromere

                        iv.       Stay together until cell divides

7.         Chromosome Numbers

            a.         Characteristic of species (pg 130)

            b.         Independent of complexity

            c.         Occur in pairs

                        i.         Made of 2 identical homologues

                        ii.        Each pair is unique

            d.         Haploid - organism has only 1 homologue

            e.         Diploid - organism has both homologues

8.         Prokaryotes

            a.         Haploid cells

            b.         DNA replicates

            c.         Cell divides into identical cells

9.         Cell Cycle

            a.         Sequence of events in life of cell

            b.         Interphase: cell growth and development

            c.         Mitosis: division of cell nucleus

            d.         Cytokinesis: cell divides

10.       Mitosis

            a.         In eukaryotes

            b.         Division of cell nucleus produces 2 identical sets of chromosomes

            c.         Normal for somatic cells

            d.         Asexual reproduction

            e.         Trigger: size of cell

11.       Interphase:

            a.         G0

                        i.         Tissues go dormant when mature

                        ii.        Nerves

            b.         Interphase: G1

                        i.         Cell becomes mature

                        ii.        Enzymes and organelles double in number

                        iii.       Cell enlarges

12.       Interphase

            a.         Interphase: S - Chromatin replicates

            b.         Interphase: G2

                        i.         Enzymes synthesized

                        ii.        Structure for mitosis develops

13.       Mitosis: Prophase

            a.         Chromatin forms chromosomes

            b.         Nucleolus and nuclear membrane disappear

            c.         Centrioles form and move to poles

            d.         Spindle fibers form

                        i.         Polar: centriole to centriole

                        ii.        Kinetochore: from kinetochore disk to centriole

            e.         Aster forms around centriole

14.       Mitosis: Metaphase

            a.         Kinetochore fibers pull chromosomes to center of cell

15.       Mitosis: Anaphase

            a.         Chromatids separate at centromere

            b.         Chromatids move to opposite poles

                        i.         Polar fibers push against each other

                        ii.        Kinetochore breaks down pulling chromatids

            c.         

16.       Mitosis: Telophase

            a.         Chromatids cluster at opposite poles

            b.         Centriole and spindles disappear

            c.         Nuclear membrane and nucleolus form

            d.         Chromatids unwind into chromatin

17.       Cytokinesis

            a.         Animal cells

                        i.         Membrane pinches in

                        ii.        Cleavage furrow splits cell in half

            b.         Plant cells

                        i.         Vesicles fuse at center, forms cell plate

                        ii.        New cell wall forms on plate

18.       Meiosis

            a.         Nuclear division that produces haploid cells

            b.         Part of sexual reproduction

            c.         Produce gametes (egg/sperm)

            d.         Interphase is normal

19.       Meiosis I: Prophase

            a.         DNA forms chromosomes

            b.         Homologues pair up: synapsis

            c.         Homologues twist together and cross over (tetrads)

            d.         Recombination

                        i.         Random mixing of genes

                        ii.        Chromosomes break and combine with each other

                        iii.       Each individual is unique

20.       Meiosis I

            a.         Metaphase: tetrads move to center of cell

            b.         Anaphase

                        i.         Tetrads separate

                        ii.        One homologue to each pole (random)

                        iii.       Still joined by centromere

            c.         Telophase

                        i.         Nuclear membrane forms

                        ii.        Cell divides

21.       Meiosis II

            a.         No DNA replication

            b.         Produces haploid germ cells

            c.         Prophase: spindle fibers form

22.       Meiosis II

            a.         Metaphase: chromosomes move to center of cell

            b.         Anaphase: chromatids split and move to poles

            c.         Telophase: nuclear membrane forms

23.       Cytokinesis

            a.         Cell Divides

            b.         Forms gametes

24.       Animal Cells

            a.         Male: spermatogensis

                        i.         4 spematids develop in meiosis

                        ii.        Develop into sperm

                        iii.       Motile

            b.         Female: Oogenesis

                        i.         Cytokinesis divides cell unevenly

                        ii.        Form 1 oocyte (egg)

                        iii.       3 polar bodies form and disintegrate

25.       Asexual Reproduction

            a.         No union of gametes

            b.         Binary fission of mitosis

            c.         Budding

            d.         Forms clone of original cell

26.       Sexual Reproduction

            a.         Gametes join chromosomes

            b.         Offspring genetic combination of parents

            c.         Produces variation

            d.         Variation increase chances of survival in changing environment