Today you will need: To turn in your homework Colored pencils (or pens) Something to write with

The Cell Cycle

Division of the Cell : All cells come from preexisting cells. Why do cells divide? Growth and Development Repair (Healing) Reproduction ( We will talk about this later in the year)

Division of the Cell : All cells come from preexisting cells. Why do cells divide? Growth and Development Humans start off as one single cell, and by the time they are adults, they have over 10 trillion cells!!! This increase in the number of cells also allows for some of those cells to be specialized for various functions. This is important to the survival of many organisms. A RESULT OF MITOSIS

Division of the Cell : All cells come from preexisting cells. Why do cells divide? Repair (Healing) Some organism, are able to regenerate lost limbs (such as arms or tails). Humans can repair skin, blood vessels and bones, or replace cells that have died. You have a “new” skin every 28 days! A RESULT OF MITOSIS

Division of the Cell : All cells come from preexisting cells. How do cells divide? PROKARYOTES EUKARYOTES Have only one circular chromosome Divide by binary fission Have a nucleus containing many chromosomes Divide by Mitosis VS.

Division of the Cell : All cells come from preexisting cells. How do cells divide? PROKARYOTES EUKARYOTES Binary fission in E. Coli Mitosis in White Fish VS.

The Cell Cycle: Eukaryotes The series of events that cells go through as they grow and divide. During the cell cycle, a cell grows, prepares for division, and divides to form two identical daughter cells, each of which then begins the cycle again.

Interphase: The longest phase of the cell cycle G0 Phase: Suspended rest period The cell is not actively dividing Includes nerve, heart and muscle cells G1 Phase: (Gap-1) Period of cell growth New proteins & organelles S Phase: (Synthesis) Chromosomes are replicated DNA synthesis G2 Phase: (Gap -2)The Shortest of the 3 phases organelles and molecules required for cell division are produced Final Preparation for Mitosis

M Phase: Division of the cell Mitosis and Cytokinesis Mitosis : Division of the nucleus consists of 4 stages Prophase Metaphase Anaphase Telophase Cytokinesis: *The division of the cytoplasm, occurs at the same time as telophase.

Cell Cycle Checkpoints Cell cycle checkpoints verify whether the processes at each phase of the cell cycle have been accurately completed before continuing into the next phase

Cell Cycle Checkpoints

The Cell Cycle G0 Phase: rest G1 checkpoint M checkpoint G2 checkpoint