Chromosomes+NLL

Chapter 18 Patterns of Chromosome Inheritance. (20 Questions total)

__pp.378-379 Chromosomes and the Cell Cycle__ G1 Stage: a cell doubles its organelles and it accumulates the materials needed for DNA synthesis. Also, various proteins are needed to change chromatin into chromosomes that are visible under the microscope when stained. A chromosome contains both proteins called histones and DNA. S Stage: DNA replication occurs; a copy is made of all the DNA in the cell. Because DNA replication occurs each chromosome consists of two identical DNA doubles helix molecules. These molecules occur in the strands called sister chromatids. Another way of expressing these events is to say that DNA replication has resulted in duplicated chromosomes. G2 Stage: the cell synthesizes the protein needed for cell division, such as the protein found in microtubules. The role of microtubules in cell division is described in a later section.
 * 1. What is interphase and what are the three stages of interphase? Describe them in detail**. Interphase is the cell cycle stage during which growth and DNA synthesis occur when the nucleus is not actively dividing.

Mitosis is a type of nuclear division. Mitosis is called duplication division because each new nucleus contains the same number and kind of chromosomes as the former cell. Cytokinesis is division of the cytoplasm. Apoptosis is the programmed cell death involving a cascade of specific cellular events leading to death and destruction of the cell.
 * 2. Define Mitosis and Cytokinesis and Apoptosis.**


 * 3. Insert a picture of the "cell cycle". Label it as: The cell cycle.**