Chapter 12
Cell Division / Mitosis
Vocabulary: gene, cell division, chromosomes, somatic cells, gametes, chromatin, sister chromatids, centromere, mitosis, cytokinesis, meiosis, mitotic phase, interphase, centrosome, aster, kinetochore, cleavage furrow, cell plate, mitotic spindle, binary fission, transformation, benign tumor, malignant tumor, metastasis
Objectives:
After attending lectures and studying the chapter, the student should be able to:
1. Define gene as it relates to the genetic material in a cell.
2. Describe the composition of the genetic material in bacteria, in archaea, and in eukaryotic cells.
3. State the location of the genetic material in prokaryotic and eukaryotic cells.
4. Distinguish between the structure of the genetic material as chromatin and as
chromosomes.
5. Distinguish between the function of the genetic material as chromatin and as
chromosomes.
6. Relating to eukaryotic cells:
a. Describe the centromere region in the genetic material.
b. State the role of cohesins in duplicated genetic material.
c. Describe the sister chromatids of a duplicated chromosome.
d. State the role of the kinetochores on the chromatids at the centromere of a duplicated
chromosome.
e. Describe spindle fibers and state their role in the separation of chromosomes during eukaryotic cell division.
f. Describe the role of centrosomes in the formation of the spindle apparatus.
g. Distinguish between a gene and an allele.
h. Describe homologous chromosomes.
i. Distinguish between an individual's genome and karyotype.
j. State the number of chromosomes in human haploid cells and in human diploid cells.
k. State which cells in humans are haploid, which cells are diploid, and which cells are neither.
7. State the two major parts of the cell cycle.
8. Describe the differences of growth characteristics between a cancerous (transformed) cell and a normal cell.
8. Relating to the prokaryotic cell cycle:
a. State the number of chromosomes in a prokaryotic cell.
b. State the cellular activities that occur during interphase.
c. Show the process of binary fission that is prokaryotic cell division.
9. Relating to the eukaryotic cell cycle:
a. Distinguish between interphase and cell division.
b. Distinguish between the G1, S, and G2 phases of interphase.
c. Define karyokinesis and cytokinesis.
d. State the two types of karyokinesis.
e. Distinguish between the M and C phases of cell division.
f. State when in the cell cycle duplication of the genetic material occurs.
10. Relating to cell division involving mitosis (mitosis + cytokinesis):
a. Define mitosis.
b. Explain why mitosis is sometimes considered "duplication division".
c. State what 1 human diploid cell becomes after mitosis plus cytokinesis.
d. State the reason humans undergo cell division involving mitosis.
e. State which cells in humans undergo cell division involving mitosis.
f. Be able to describe, draw, and recognize the 4 stages of mitosis.
g. Describe the cleavage-furrow process of cytokinesis in animal cells.
h. Describe the cell-plate process of cytokinesis in plant cells.
| 1142034827 | Cell Cycle | An ordered sequence of events in the life of a cell |  | 1 |
| 1142034828 | Mitosis | A process of nuclear division in eukaryotic cells conventionally divided into five stages: prophase, prometaphase, metaphase, anaphase, and telophase. Mitosis conserves chromosome number by allocating replicated chromosomes equally to each of the daughter nuclei. |  | 2 |
| 1142034829 | What are the five stages of mitosis? | PPMAT Prophase Prometaphase Metaphase Anaphase Telophase |  | 3 |
| 1142034830 | Prophase | The first stage of mitosis, in which the chromatin condenses into discrete chromosomes visible with a light microscope, the mitotic spindle begins to form, and the nucleolus disappears but the nucleus remains intact. |  | 4 |
| 1142034831 | Prometaphase | The second stage of mitosis, in which the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the chromosomes. |  | 5 |
| 1142034832 | Metaphase | The third stage of mitosis, in which the spindle is complete and the chromosomes, attached to microtubules at their kinetochores, are all aligned at the metaphase plate. |  | 6 |
| 1142034833 | Anaphase | The fourth stage of mitosis, in which the chromatids of each chromosome have separated and the daughter chromosomes are moving to the poles of the cell. |  | 7 |
| 1142034834 | Telophase | The fifth and final stage of mitosis, in which daughter nuclei are forming and cytokinesis has typically begun. |  | 8 |
| 1142034835 | Cytokinesis | The division of the cytoplasm to form two separate daughter cells immediately after mitosis, meiosis I, or meiosis II. |  | 9 |
| 1142034836 | Cell Division | The reproduction of cells |  | 10 |
| 1142034837 | Genome | The genetic material of an organism or virus; the complete complement of an organism's or virus's genes along with its noncoding nucleic acid sequence |  | 11 |
| 1142034838 | Chromosomes | A cellular structure carrying genetic material, found in the nucleus of eukaryotic cells. Each chromosome consists of one very long DNA molecule and associated proteins |  | 12 |
| 1142034839 | Chromatin | The complex of DNA and proteins that makes up eukaryotic chromosomes. When the cell is not dividing, chromatin exists in its dispersed form, as a mass of very long, thin fibers that are not visible with a light microscope |  | 13 |
| 1142034840 | Somatic Cells | Any cell in a multicellular organism except a sperm or egg or their precursors. |  | 14 |
| 1142034841 | Gametes | A haploid reproductive cell, such as an egg or sperm. Gametes unite during sexual reproduction to produce a diploid zygote. |  | 15 |
| 1142034842 | Sister Chromatids | Two copies of a duplicated chromosome attached to each other by proteis at the centromere and sometimes, along the arms. While joined, two sister chromatids make up one chromosome. Chromatids are eventually separated during mitosis or meiosis II |  | 16 |
| 1142034843 | Centromere | In a duplicated chromosome, the region on each sister chromatid where they are most closely attached to each other by proteins that bind to specific DNA sequences; this close attachment causes a constriction in the condensed chromosome. (An uncondensed, unduplicated chromosome has a single centromere, identified by its DNA sequence.) |  | 17 |
| 1142034844 | How many chromatids are in a duplicated chromosome? | 2 | | 18 |
| 1142034845 | mitotic (M) phase | The phase of the cell cycle that includes mitosis and cytokinesis. |  | 19 |
| 1142034846 | interphase | The period in the cell cycle when the cell is not dividing. During interphase, cellular metabolic activity is high, chromosomes and organelles are duplicated, and cell size may increase. Interphase often accounts for about 90% of the cell cycle. |  | 20 |
| 1142034847 | mitotic spindle | An assemblage of microtubules and associated proteins that is involved in the movement of chromosomes during mitosis. |  | 21 |
| 1142034848 | Transformation | (1) The conversion of a normal animal cell to a cancerous cell. (2) A change in genotype and phenotype due to the assimilation of external DNA by a cell. When the external DNA is from a member of a different species, transformation results in horizontal gene transfer | 22 | |
| 1142034849 | anchorage dependence | The requirement that a cell must be attached to a substratum in order to initiate cell division. |  | 23 |
| 1142034850 | aster | A radial array of short microtubules that extends from each centrosome toward the plasma membrane in an animal cell undergoing mitosis. |  | 24 |
| 1142034851 | benign tumor | A mass of abnormal cells with specific genetic and cellular changes such that the cells are not capable of surviving at a new site and generally remain at the site of the tumor's origin. | 25 | |
| 1142034852 | binary fission | A method of asexual reproduction by "division in half." In prokaryotes, binary fission does not involve mitosis, but in single-celled eukaryotes that undergo binary fission, mitosis is part of the process. |  | 26 |
| 1142034853 | cleavage | (1) The process of cytokinesis in animal cells, characterized by pinching of the plasma membrane. (2) The succession of rapid cell divisions without significant growth during early embryonic development that converts the zygote to a ball of cells. |  | 27 |
| 1142034854 | density-dependent inhibition | The phenomenon observed in normal animal cells that causes them to stop dividing when they come into contact with one another. | 28 | |
| 1142034855 | growth factor | (1) A protein that must be present in the extracellular environment (culture medium or animal body) for the growth and normal development of certain types of cells. (2) A local regulator that acts on nearby cells to stimulate cell proliferation and differentiation. | 29 | |
| 1142034856 | kinetochore | A structure of proteins attached to the centromere that links each sister chromatid to the mitotic spindle. |  | 30 |
| 1142034857 | malignant tumor | A cancerous tumor containing cells that have significant genetic and cellular changes and are capable of invading and surviving in new sites. Malignant tumors can impair the functions of one or more organs. | 31 | |
| 1142034858 | Metaphase plate | An imaginary structure located at a plane midway between the two poles of a cell in metaphase on which the centromeres of all the duplicated chromosomes are located. |  | 32 |
| 1142034859 | Metastasis | The spread of cancer cells to locations distant from their original site. |  | 33 |
| 1142034860 | MPF | Maturation-promoting factor (or M-phase-promoting factor); a protein complex required for a cell to progress from late interphase (G2) to mitosis. The active form consists of cyclin and a cyclin dependent kinase. | 34 | |
| 1142034861 | origin of replication | Site where the replication of a DNA molecule begins, consisting of a specific sequence of nucleotides. Prokaryotic DNA has only one while eukaryotic DNA has many. | 35 | |
| 1142034862 | somatic cell | Any cell in a multicellular organism except a sperm or egg or their precursors. | 36 | |
| 1142034863 | transformation | (1) The conversion of a normal animal cell to a cancerous cell. (2) A change in genotype and phenotype due to the assimilation of external DNA by a cell. When the external DNA is from a member of a different species, transformation results in horizontal gene transfer. | 37 | |
| 1142034864 | asexual reproduction | A type of reproduction involving only one parent that produces genetically identical offspring by budding or by the division of a single cell or the entire organism into two or more parts. | 38 | |
| 1142034865 | sexual reproduction | A type of reproduction in which two parents give rise to offspring that have unique combinations of genes inherited from the gametes of the two parents. | 39 | |
| 1142034866 | diploid cell | A cell containing two sets of chromosomes (2n), one set inherited from each parent. | 40 | |
| 1142034867 | haploid cell | A cell containing only one set of chromosomes (n). | 41 | |
| 1142034868 | Meiosis | Meiosis is essential to sex, because it enables each parent to contribute one set of chromosomes-- half the total-- to each diploid offspring. | 42 | |
| 1142034869 | G1 Phase | The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins. | 43 | |
| 1142034870 | S Phase | The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated. | 44 | |
| 1142034871 | G2 Phase | The second gap, or growth phase, of the cell cycle, consisting of the portion of interphase after DNA synthesis occurs. | 45 | |
| 1142034872 | Centrosome | A structure present in the cytoplasm of animal cells that functions as a microtubule-organizing center and is important during cell division. A centrosome has two centrioles. | 46 | |
| 1142034873 | Metaphase Plate | An imaginary structure located at a plane midway between the two poles of a cell in metaphase on which the centromeres of all the duplicated chromosomes are located. | 47 | |
| 1142034874 | Cleavage Furrow | The first sign of cleavage in an animal cell; a shallow groove around the cell in the cell surface near the old metaphase plate. | 48 | |
| 1142034875 | Cell Plate | A membrane-bounded, flattened sac located at the midline of a dividing plant cell, inside which the new cell wall forms during cytokinesis. | 49 | |
| 1142034876 | Binary Fission | A method of asexual reproduction by "division in half." In prokaryotes, binary fission does not involve mitosis, but in single-celled eukaryotes that undergo binary fission, mitosis is part of the process. | 50 | |
| 1142034877 | Cell cycle control system | A cyclically operating set of molecules in the eukaryotic cell that both triggers and coordinates key events in the cell cycle. | 51 | |
| 1142034878 | Checkpoint | A control point in the cell cycle where stop and go-ahead signals can regulate the cycle. |  | 52 |
| 1142034879 | G0 Phase | A nondividing state occupied by cells that have left the cell cycle, sometimes reversibly. |  | 53 |
| 1142034880 | Cyclin | A cellular protein that occurs in a cyclically fluctuating concentration and that plays an important role in regulating the cell cycle. |  | 54 |
| 1142034881 | Cyclin-dependent kinases | A protein kinase that is active only when attached to a particular cyclin. When its cyclin is attached together they form the maturation promoting factor (MPF). |  | 55 |
| 1142034882 | Growth Factor | (1) A protein that must be present in the extracellular environment (culture medium or animal body) for the growth and normal development of certain types of cells. (2) A local regulator that acts on nearby cells to stimulate cell proliferation and differentiation. | 56 | |
| 1142034883 | Density Dependent Inhibition | The phenomenon observed in normal animal cells that causes them to stop dividing when they come into contact with one another. | 57 | |
| 1142034884 | Anchorage Dependence | The requirement that a cell must be attached to a substratum in order to initiate cell division. | 58 |
