Bienvenue Today you will need: Your science notebook Your electronics in the charging station The paper from the welcome table

Mitosis

What are Chromosomes? Sister Chromatids Chromosomes Carry the genetic information (traits) that are passed on from one generation of cells to the next. Chromatids A chromatid is one half of a chromosome Each pair of chromatids is attached at an area called the centromere. Centromere Sister Chromatids

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

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

Prophase Significant Events Plant Nuclear Envelope breaks down Nucleolus disappears Chromosomes become visible *Centrioles move to the poles of the cell (Animals Only) Nuclear Envelope Animal

Metaphase Significant Events Plant Chromosomes line up across the center of the cell (metaphase plate) Spindle fibers (apparatus) connect to each chromosome at the centromere Spindle Animal

Metaphase Chases

Anaphase Significant Events Plant Chromosomes are separated and pulled to opposite sides of the cell by the spindle fibers This phase ends when the chromosomes stop moving Animal

Anaphase Changes

Mitosis is complete, cell division is not. Telophase Plant Significant Events Chromosomes uncoil Two new nuclear envelopes form Mitosis is complete, cell division is not. CYTOKINESIS Division of the cytoplasm Occurs at the same time as telophase Plants: Cell plate forms Animals: Cleavage furrow forms Animal

VS. Cytokinesis Animal Plant The cell membrane pinches in to form a cleavage furrow A cell plate forms midway between the divided nuclei.