Ch. 10 – Cell Division and Growth Cell Growth usually involves an organism making MORE cells. The size a cell reaches is limited by the cell’s surface area to volume ratio. As the cell grows, its surface area doesn’t grow as quickly as its volume does (therefore, its surface area to volume ratio DECREASES as it grows in size).
Ratio of Surface Area to Volume in Cells Section 10-1 Cell Size Surface Area (length x width x 6) Volume (length x width x height) Ratio of Surface Area to Volume Go to Section:
If a cell gets too big, the surface area of its membrane cannot bring oxygen and nutrients fast enough to meet the needs of its volume. The cell will divide when it gets too big through a process called mitosis. Cell growth can also be limited by nutrient availability and space. Cell division can be regulated by proteins called kinases. Uncontrolled cell growth can result in cancer.
Figure 10–4 The Cell Cycle Section 10-2 G1 phase M phase S phase Go to Section:
Chromosome structure before cell division. Two identical, “sister” chromatids. Holds sister chromatids together in the middle.
PROPHASE
METAPHASE
Figure 10–5 Mitosis and Cytokinesis Section 10-2 Spindle forming Centrioles Chromatin Centromere Nuclear envelope Centriole Chromosomes (paired chromatids) Interphase Prophase Spindle Cytokinesis Centriole Metaphase Telophase Individual chromosomes Anaphase Nuclear envelope reforming Go to Section:
Figure 10–5 Mitosis and Cytokinesis Section 10-2 Spindle forming Centrioles Chromatin Centromere Nuclear envelope Centriole Chromosomes (paired chromatids) Interphase Prophase Spindle Cytokinesis Centriole Metaphase Telophase Individual chromosomes Anaphase Nuclear envelope reforming Go to Section:
Figure 10–5 Mitosis and Cytokinesis Section 10-2 Spindle forming Centrioles Chromatin Centromere Nuclear envelope Centriole Chromosomes (paired chromatids) Interphase Prophase Spindle Cytokinesis Centriole Metaphase Telophase Individual chromosomes Anaphase Nuclear envelope reforming Go to Section:
Figure 10–5 Mitosis and Cytokinesis Section 10-2 Spindle forming Centrioles Chromatin Centromere Nuclear envelope Centriole Chromosomes (paired chromatids) Interphase Prophase Spindle Cytokinesis Centriole Metaphase Telophase Individual chromosomes Anaphase Nuclear envelope reforming Go to Section:
Figure 10–5 Mitosis and Cytokinesis Section 10-2 Spindle forming Centrioles Chromatin Centromere Nuclear envelope Centriole Chromosomes (paired chromatids) Interphase Prophase Spindle Cytokinesis Centriole Metaphase Telophase Individual chromosomes Anaphase Nuclear envelope reforming Go to Section:
Figure 10–5 Mitosis and Cytokinesis Section 10-2 Spindle forming Centrioles Chromatin Centromere Nuclear envelope Centriole Chromosomes (paired chromatids) Interphase Prophase Spindle Cytokinesis Centriole Metaphase Telophase Individual chromosomes Anaphase Nuclear envelope reforming Go to Section:
Cell Cycle Section 10-2 Go to Section: includes M phase (Mitosis) Interphase is divided into is divided into G1 phase S phase Prophase G2 phase Metaphase Telophase Anaphase Go to Section:
link to mitosis animation Fruit Tree Grafting Sea Star regeneration Link to animation review of meiosis http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter3/animation__how_meiosis_works.html Link to animation of mitosis/meiosis comparison http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter3/animation__comparison_of_meiosis_and_mitosis__quiz_1_.html
Budding in Hydra
There are 2 types of Reproduction: Asexual Sexual________ One parent contributes Genetic info. to offspring Two parents contribute genetic info. to offspring Offspring are identical to each other an parent Offspring are similar to each other an parent Mitosis is used to make offspring cells Meiosis is used by each parent to make sex cells called gametes which fuse into a cell that grows into offspring. Ex: plants, some animlas, protists, bacteria Ex: animals, plants
MEIOSIS Meiosis is a special type of cell division used to make sex cells called gametes. Meiosis is used to give sex cells half the species' normal chromosome number.
Background Information on Chromosomes - Humans have 46 chromosomes in each body cell. - These 46 chromosomes are organized into 23 pairs. These are known as homologous pairs. - In each pair humans have, one of the chromosomes was donated from mom's egg and one from dad's sperm.
Pairs of chromosomes contain information for the same types of traits. During meiosis, homologous chromosomes will be separated and only one will be passed to each sex cell that is made.
Figure 11-15 Meiosis Meiosis I Interphase I Section 11-4 Prophase I Metaphase I Anaphase I Cells undergo a round of DNA replication, forming duplicate Chromosomes. Each chromosome pairs with its corresponding homologous chromosome to form a tetrad. Spindle fibers attach to the chromosomes. The fibers pull the homologous chromosomes toward the opposite ends of the cell. Go to Section:
Figure 11-15 Meiosis Meiosis I Interphase I Section 11-4 Prophase I Metaphase I Anaphase I Cells undergo a round of DNA replication, forming duplicate Chromosomes. Each chromosome pairs with its corresponding homologous chromosome to form a tetrad. Spindle fibers attach to the chromosomes. The fibers pull the homologous chromosomes toward the opposite ends of the cell. Go to Section:
Figure 11-15 Meiosis Meiosis I Interphase I Section 11-4 Prophase I Metaphase I Anaphase I Cells undergo a round of DNA replication, forming duplicate Chromosomes. Each chromosome pairs with its corresponding homologous chromosome to form a tetrad. Spindle fibers attach to the chromosomes. The fibers pull the homologous chromosomes toward the opposite ends of the cell. Go to Section:
DNA Replication occurs during S phase. Figure 11-15 Meiosis Section 11-4 Meiosis I Interphase I Prophase I Metaphase I Anaphase I DNA Replication occurs during S phase. Chromosomes first appear in their homologous pairs Chromosomes line up down the middle of the cell in their homologous pairs Homolopgous chromosomes are separated to opposite ends of the cell Go to Section:
Figure 11-17 Meiosis II Meiosis II Section 11-4 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. Go to Section:
Figure 11-17 Meiosis II Meiosis II Section 11-4 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. Go to Section:
Figure 11-17 Meiosis II Meiosis II Section 11-4 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. Go to Section:
Figure 11-17 Meiosis II Meiosis II Section 11-4 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. Go to Section:
Chromosomes line up single file down the middle of the cell Figure 11-17 Meiosis II Section 11-4 Meiosis II Telophase II/ cytokinesis TelophaseI/ Prophase II Metaphase II Anaphase II Meiosis II results in four daughter cells, each with half the genetic information of the parent cell. Chromosomes line up single file down the middle of the cell Sister chromatids are separated to opposite ends of the cell Homologous chromosomes have been separated Go to Section:
Meiosis Vocabulary Synapsis - A process where homologous chromosomes pair up with each other during prophase I Tetrad - A structure formed from "paired up" homologous chromosomes. XX
Diploid - A term used to describe the normal species chromosome number (for organisms with their chromosomes in pairs). The human diploid number is 46. Haploid (n)- A term used to describe a cell with one copy of each type of chromosome.
There are 2 ways that meiosis introduces variety into sex cells: 1. Independent Assortment – a process where the homologous pairs of chromosomes can line up on either side of the metaphase plate. For example: X = mom donated X = dad donated XX XX
Crossing-Over Section 11-4 2. Crossing Over: A process where homologous chromosomes cross over and exchange chromosome parts during meiosis I. Go to Section:
Meiosis is different in females and males: Males Females