Mitosis Asexual cell division Begins in the nucleus

Mitosis Asexual cell division!! Begins in the nucleus of a cell.

How does asexual reproduction occur in humans? • MITOSIS – Skin cells – Liver cells

MITOSIS 1. Occurs in somatic (body) cells. 2. Does not create sperm and egg. 3. Creates exact copies of a parent cell 4. Used to repair wounds and grow from a zygote to a person. 5. DNA duplicates itself and then the cell divides

MITOSIS

Mitosis and the Cell Cycle Remember the letters: I P M A T These letters will help you to remember the order of the 5 stages of the Cell Cycle: 1. Interphase 1. Prophase 1. Metaphase 1. Anaphase 1. Telophase

Interphase: Called Resting phase Cell is NOT dividing Performs life functions - Cell grows - Copies all organelles - Copies DNA

1. Interphase: “Prep Period” - Cell preparation for cell division - Two Major Events: 1. Cell increases in size 2. DNA and organelles are replicated (copied) Chromatin: are chromosomes when they are NOT distinguishable and they look like spaghetti.

Interphase has 3 parts (takes up about 90% of the cell cycle) 1. G 1 - growth one phase (organelles grow) 2. S - synthesis phase (replication of chromosome material) 3. G 2 - growth phase two (more organelle and cell growth)

MITOSIS - Has 4 phases - Prophase, Metaphase, Anaphase, Telophase

Prophase: - DNA changes from chromatin to chromosome - Nucleus breaks apart with nucleolus and nuclear membrane disappears - Centrioles begin to separate and move to poles - Spindle fibers form to connect centrioles

Terms: • Chromatid: each chromosome strand • Centromere: (kinetochore): holds the chromatids together

Metaphase: (M is for Middle) • Chromosomes line up along the equator (middle) • Chromosomes attach to the spindle fibers at their centromeres

Anaphase: ( A is for Away) • Spindle fibers pull chromosomes apart and move each half of the chromosomes to opposite poles

Telophase: the reverse of interphase • Nuclear membrane form around each set of chromosomes • DNA changes from chromosomes to chromatin • Spindle fibers disappear Plant cells -

CYTOKINESIS • the cell membrane pinches in to split the parent cell into two daughter cells.

Compare & Contrast Mitosis in Plants and Animals

Plant vs Animal Plant Animal No centrioles = no Centrioles spindle fibers No astray rays b/c there Astray rays are no centrioles Forms a cell plate Cytokinesis to pinch in cell membrane

Asexual Reproduction: Mitosis •