Biology 100/101
Lecture 9: Cell Reproduction
(Print Version)

Announcements &
Assignments

Lecture Objectives

Web Resources

DNA

Chromosomes

Cell Cycle

Control of
the Cell Cycle

Stem Cells

Cancer Cells

Lecture Syllabus

IB 100/101 Home Page

Text Readings in Lewis, et. al.

Chapter 9, The Cell Cycle
Chapter 13, DNA Structure and Function, pgs. 231-238 and fig. 13.11

The "Reviewing Concepts" boxes are valuable summaries of the main ideas in these sections of the text.

You have open access (no log-in or password needed) to instructional materials on the Text web site. Select the text chapter you want and use the links to the e-learning modules or other available materials. There is also a collection of study materials called the "Essential Study Partner" that you may find useful.

Web Crossing

You may also ask questions and see answers to your classmates' questions in Web Crossing in the "Talk to Sarah and Ed" discussion.

Objectives:

The content of this lecture will help you complete this assignment:

Take-Home Assignment #4 - Meiosis and Genetics Due at Lecture Monday October 15

After studying this material you should be able to:

1. Draw a diagram, create a concept map, or write a paragraph that explains the relationships among these terms;

chromosomes	sister chromatids	centromeres
telomeres	DNA	nucleotides
bases (A, C, G, T)	complementary base pairing	sugar (deoxyribose)
phosphate group	semi-conservative DNA replication	cell cycle

2. Use common objects such as pencils or paper clips to model the replication and movement of chromosomes in a cell through all stages of the cell cycle.

3. Using your body as a model organism, describe where we would find cells undergoing mitosis and where we would find cells that are not likely to be dividing.

4. Describe the mechanisms by which cell division is controlled in your body.

5. Define the term, apoptosis, and describe the role of this process in normal human development.

6. Describe the special characteristics and functions of stem cells.

Web resources for cell reproduction:

• Genetics News Network (GNN) - a good source of news and information!

• Mitosis: an illustration of the mitotic process provided by Access Excellence.

• Mitosis Animation from Sumanasinc.com

• Cell Division Exercise from biologyinmotion.com/

• Cell Division: Binary Fission And Mitosis. This document,from An On-line Biology Book, is an text description of cell division with some nice drawings and lots of mitosis links at the very bottom of the page.

• The Biology Project - Cell Biology from the University of Arizona. The Biology Project is an interactive online resource for learning biology, developed at The University of Arizona.

• Visit cellsalive.com. Select the Mitosis link

• Visit cellsalive.com. Select the Cell Cycle link

• Interactive Chromosome/Gene Poster from Gene Gateway - Exploring Genes and Genetic Disorders

What is DNA, Why do we need it, and Where does it come from?

• Nucleotide & Complementary Base Pairing - A-T & C-G (Lewis, et. al. Page 233, fig. 13.7)

• Each DNA Nucleotide includes:

• One Base (A, C, G, & T)

• One Sugar (Deoxyribose)

• One Phosphate group

How does DNA replicate?

Lewis, et. al., pg 237, figure 13.13

• Semiconservative DNA Replication

• Semiconservative DNA Replication: The Movie

• The Collaboration of Proteins During Semiconservative Replication [of DNA]

• DNA Wrapping and DNA Replication Movie

What are Chromosomes?

• What are chromosomes made of? (See Lewis, et. al. pg 235, figure 13.11

• Human Chromosomes Lewis, et. al. Page 168, figure 10.5

• You get one chromosome of each type (1-22, plus X and Y) from your mother in her egg and one from your father in his sperm.

• Single or Replicated Chromosomes? Lewis, et. al. Page 149, figure 9.4

• Chromosome structure Lewis, et. al. Page 209, figure 12.1

• Chromatids (sister chromatids)

• Sister chromatids are produced by semiconservative DNA replication

• Sister chromatids are exact copies of the original DNA molecule

• Centromeres

• Telomeres

• Interactive Chromosome/Gene Poster from Gene Gateway - Exploring Genes and Genetic Disorders

The Life of a Cell:
Cell Division, Cell Maturation, and Cell Death (Apoptosis)

• Visit cellsalive.com and select Cell Cycle

• The Cell Cycle from geneticsolutions.com

Note the form of the chromosomes (duplicated or not) at each phase of the cell cycle.

• Cell Cycle Diagram Lewis, et. al. Page 147, fig. 9.2

• Interphase

• G1 (Growth)

• S (Synthesis)

• G2 (Growth)

• Mitosis Animation

• Synchronized Swimming Mitosis

• Mitosis - first half text pg. 150, fig. 9.7

• Mitosis - Second half text pg. 150, fig. 9.7

• Prophase

• Metaphae

• Anaphase

• Telophase

• Mitosis in relation to the cell cycle from geneticsolutions.com

Note the form of the chromosomes (duplicated or not) at the beginning, during, and at the end of mitosis.

• Other mitosis resources

• Mitosis Animation from Sumanasinc.com

• Cell Division Exercise from biologyinmotion.com/

• Mitosis from The On-line Biology Book

• Mitosis from the University of Arizona Biology Project

Control of Cell Division

• Cell Cycle Check Points Lewis, et. al. pg. 153, fig. 9.10

• Visit cellsalive.com. Select Cell Cycle - then on the cell cycle screen select Checkpoints.

• Cellular Clock - Telomeres

  Telomeres and cell division Lewis, et. al. pg. 154, fig. 9.11

• Effect of Neighboring Cells - Contact Inhibition Lewis, et. al. pg. 155, fig. 9.12

• Extra Cellular Influences

• Hormones

• Hormone levels control ovulation, celldivision, and apoptosis in building and degrading the endometrium. Lewis, et. al. pg. 807, fig.41.8

• Growth Factors

• Cancer cells produce growth factors that stimulate cell division in nearby blood vessels, resulting in a blood supply for the tumor.

• Intracellular Influences

• Kinases and Cyclins Lewis, et. al. pg. 156, fig. 9.13

Cell Death - Apoptosis

• Cell division adds cells - Apoptosis removes cells Text Pg. 146, fig 9.1

• Normal cell death in damaged cells from geneticsolutions.com

• Apoptosis and "clean up" by white blood cells from geneticsolutions.com

• Cell Death- Apoptosis helps direct development of an organism Text Pg. 157, fig 9.15

Stem Cells

Text, Pg. 156, fig. 9.14

• Cell Populations

• Renewal Cell Populations (digestive tract)

• Expanding Cell Populations (Repair, young organisms, some adult kidney, liver, pancreas, and bone marrow)

• Static Cell Populations (Nerve & Muscle cells - stuck in G1)

What are Stem Cells? from Sumanasinc.com

The Stem Cell Institute

Cancer Treatments Concentrate on Control of Cell Cycle

• Development of cancer Text, pg. 153, fig, 8.17

• Control of DNA Replication

• Preventing Cell Division

• See OncoLink, Cancer Causes, Screening, and Prevention from the University of Pennsylvania.

• Informtion about cancer and cancer treatments from the U.S. Food and Drug Administration - Center for Drug Evaluation and Research