Interpret Visuals The diagram shows a phase of mitosis. Use the diagram to answer the following questions.
Identify the phase of mitosis shown in the diagram.
Is this a plant or animal cell? How do you know?
The four chromosomes shown in the center of this cell each have two connected strands. Explain how the two strands on the same chromosome compare with regard to the genetic information they carry. In your answer, be sure to explain why this is important to the cell.
10.3 Regulating the Cell Cycle
Understand Key Concepts
The timing in the cell cycle in eukaryotic cells is believed to be controlled by a group of closely related proteins known as
chromatids.
cyclins.
centromeres.
centrioles.
In the cell cycle, external regulatory proteins direct cells to
speed up or slow down the cell cycle.
remain unchanged.
proceed and then stop the cell cycle.
grow uncontrollably.
When some cells are removed from the center of a tissue culture, will new cells replace the cells that were removed? Explain.
Describe the role of cyclins.
Think Critically
Compare and Contrast How do cancer cells differ from noncancerous cells? How are they similar?
Predict A cell will usually undergo apoptosis if the cell experiences DNA damage that could lead to a tumor. Predict what may happen if a gene that controls apoptosis is damaged.
solve the CHAPTER MYSTERY
PET SHOP ACCIDENT
Julia kept a close eye on the injured salamander. About a month after the accident, Julia realized that a new limb was growing to replace the lost one! Salamanders are one of only a few vertebrates that can regenerate a complete limb. Examine the illustrations that show how a new limb develops. Then answer the questions.
Week 1: Dedifferentiation
At first, cells in the injured limb undergo dedifferentiation. During this process, cells such as muscle cells and nerve cells lose the characteristics that make them specialized.
Week 3: Blastema Formation
The dedifferentiated cells migrate to the wounded area and form a blastema—a growing mass of undifferentiated cells.
Week 5: Redifferentiation
Cells in the blastema then redifferentiate and form the tissues needed for a mature limb. The limb will continue to grow until it is full size.
Relate Cause and Effect Why is dedifferentiation of the salamander's limb cells necessary before regeneration can occur?
Classify What type of cells do you think are contained in the blastema? Explain.
Connect to the
Unlike salamanders, planarians contain undifferentiated cells throughout their adult bodies. How might the regeneration process in salamanders and planarians differ?
Table of Contents
- Formulas and Equations
- Applying Formulas and Equations
- Mean, Median, and Mode
- Estimation
- Using Measurements in Calculations
- Effects of Measurement Errors
- Accuracy
- Precision
- Comparing Accuracy and Precision
- Significant Figures
- Calculating With Significant Figures
- Scientific Notation
- Calculating With Scientific Notation
- Dimensional Analysis
- Applying Dimensional Analysis