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

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

Answers to many of these questions can be found at the Text On-Line Learning Center

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

Lecture Activity: Coupling of photosynthesis and respiration

Biomass accumulation in bean plants:

Seeds germinated in dark and light
Germination Data Table

How do you explain the biomass decrease of bean plants in the dark versus the light?
• PRINT your name in one corner of a sheet of paper
• SIGN your name in the same corner of the paper
• Hand in the sheet when asked to do so.

Objectives:

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.
• 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

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 227, fig. 12.7)
• Each DNA Nucleotide includes:
• One Base (A, C, G, & T)
• One Sugar (Deoxyribose)
• One Phosphate group
• The Double Helix

How does DNA replicate?

Lewis, et. al., pg 236, figure 12.14

• DNA Replication
• DNA Replication: The Movie
• The Collaboration of Proteins During Replication [of DNA]

What are Chromosomes?

• What are chromosomes made of? (See Lewis, et. al. pg 231, figure 12.11
• Human Chromosomes Lewis, et. al. Page 201
• Single or Replicated Chromosomes?
• Chromosome structure
• Chromatids (sister chromatids)
• Centromeres
• Telomeres

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

• Cell Cycle Diagram Lewis, et. al. Page 139, fig. 8.2
• Visit cellsalive.com and select Cell Cycle
• Interphase
• G1 (Growth)
• S (Synthesis)
• G2 (Growth)
• Mitosis - first half text pg. 12. fig. 8.7
• Mitosis - Second half text pg. 12. fig. 8.7
• Prophase
• Metaphae
• Anaphase
• Telophase
• Other mitosis resources
• Mitosis from The On-line Biology Book
• Visit cellsalive.com. Select Mitosis.
• Mitosis from the University of Arizona Biology Project

Control of Cell Division

• Cell Cycle Check Points Lewis, et. al. pg. 146, fig. 8.10
• Visit cellsalive.com. Select Cell Cycle - then on the cell cycle screen select Checkpoints.
• Cellular Clock - Telomeres

  Telomeres and cell division

• Effect of Neighboring Cells - Contact Inhibition
• Extra Cellular Influences
• Hormones
• Growth Factors
• Intracellular Influences
• Kinases and Cyclins

Stem Cells

Text, Pg. 150, fig. 814

• 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)

• Cell Death- Apoptosis Text Pg. 151, fig 8.15

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 ("bogus" DNA nucleotides)
• Preventing Cell Division (chemicals or radiation that disrupt cancer cells as they divide)
• Apoptosis and Cancer

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