Click on a lesson name to select. Cellular Reproduction Section 1: Cellular Growth Section 2: Mitosis and Cytokinesis Section 3: Cell Cycle Regulation

Cellular Growth Ratio of Surface Area to Volume Section 1 Cellular Reproduction

 As the cell grows, its *.  The cell might have difficulty supplying nutrients and expelling enough waste products. Section 1 Cellular Growth

Transport of Substances  Substances move by diffusion or by motor proteins.  Diffusion over large distances is slow and inefficient. Cellular Reproduction  Small cells maintain more efficient transport systems. Section 1 Cellular Growth

Cellular Communications  The need for signaling proteins to move throughout the cell also limits cell size.  Cell size affects the ability of the cell to * Cellular Reproduction Section 1 Cellular Growth

The Cell Cycle  Cell division prevents the cell from becoming too large.  It also is the way the cell reproduces so that you grow and heal certain injuries. Cellular Reproduction  * called the cell cycle. Section 1 Cellular Growth

 Interphase is the stage during which the *.  Mitosis is the stage of the cell cycle during which the *. Cellular Reproduction Section 1 Cellular Growth  Cytokinesis is the method by which *.

Cellular Reproduction The Stages of Interphase  The first stage of interphase, G 1  The cell is growing, carrying out normal cell functions, and preparing to replicate DNA. Section 1 Cellular Growth

Cellular Reproduction The Second Stage of Interphase, S  The cell copies its DNA in preparation for cell division. Section 1 Cellular Growth

Cellular Reproduction The Third Stage of Interphase, G 2  The cell prepares for the division of its nucleus. Section 1 Cellular Growth

Mitosis and Cytokinesis Cellular Reproduction The Stages of Mitosis  Prophase  *.  Sister chromatids are attached at the centromere.  Spindle fibers form in the cytoplasm. Section 2

Cellular Reproduction  The nuclear envelope seems to disappear.  *. Section 2 Mitosis and Cytokinesis

Cellular Reproduction Metaphase  Sister chromatids are pulled along the spindle apparatus toward the center of the cell.  *. Section 2 Mitosis and Cytokinesis

Cellular Reproduction Anaphase  The microtubules of the spindle apparatus begin to shorten.  *. ** Section 2 Mitosis and Cytokinesis

Cellular Reproduction Telophase **  Two new nuclear membranes begin to form and the nucleoli reappear.  The spindle apparatus disassembles. Section 2 Mitosis and Cytokinesis

Cellular Reproduction Cytokinesis  In animal cells, microfilaments constrict, or pinch, the cytoplasm.  In plant cells, a new structure, called a cell plate, forms. Section 2 Mitosis and Cytokinesis

Cell Cycle Regulation Cellular Reproduction Normal Cell Cycle  Different cyclin/CDK combinations signal other activities, including * Section 3

Cellular Reproduction Quality Control Checkpoints  The cell cycle has built-in checkpoints that monitor the cycle and can stop it if something goes wrong.  Spindle checkpoints also have been identified in mitosis. Section 3 Cell Cycle Regulation

Cellular Reproduction Abnormal Cell Cycle: Cancer  Cancer is *.  Cancer cells can kill an organism by crowding out normal cells, resulting in the loss of tissue function. Section 3 Cell Cycle Regulation

Cellular Reproduction Causes of Cancer  The changes that occur in the regulation of cell growth and division of cancer cells are due to mutations. ** Section 3 Cell Cycle Regulation

Cellular Reproduction Apoptosis **  Cells going through apoptosis actually shrink and shrivel in a controlled process. Section 3 Cell Cycle Regulation

Cellular Reproduction Stem Cells  * when under the right conditions Section 3 Cell Cycle Regulation

Cellular Reproduction Embryonic Stem Cells  After fertilization, the resulting mass of cells divides repeatedly until there are about 100–150 cells. These cells have not become specialized. Section 3 Cell Cycle Regulation

Cellular Reproduction Adult Stem Cells  Found in various tissues in the body and might be used to maintain and repair the same kind of tissue  Less controversial because the adult stem cells can be obtained with the consent of their donor Section 3 Cell Cycle Regulation