Mitosis with Yarn! Mr. Levine Stages of Mitosis to Model - PowerPoint PPT Presentation

Mitosis with Yarn! Mr. Levine

Stages of Mitosis to Model • Interphase (Growth + Synthesis) • Prophase • Metaphase • Anaphase • Telophase • Cytokinesis • Mnemonics (memory tricks)? – I nteresting P eople M ake A T errific C onversation – I P ropose M en A re T oads ( C ) – I t P robably M eans A nother T est ( C )

Cell has grown, ready to divide! • Hanging in the nucleus are copies of each chromosome • Goal: make two cells with complete chromosome sets • What needs to happens first?

Interphase - Synthesis • DNA gets copied NEXT?

Prophase • Nuclear membrane dissolves • DNA condenses • Centrioles/Spindles form (from cytoskeleton) NEXT?

Metaphase • Chromosomes, organized by centrioles and spindle fibers, line up on metaphase plate NEXT?

Anaphase • Chromatids separate and are pulled to opposite ends of cell by centrioles/spindles NEXT?

Telophase • Chromosomes spread back out • Nuclear envelopes reappear • Centrioles/Spindles disappear (back to cytoskeleton) Final step?

Cytokinesis - Animals • Cleavage furrow forms, cells separate

Cytokinesis - Plants • Cell plate forms between daughter cells

Now it’s your turn! • Yarn in packets – Short Red (2x) – chromosomes (6 cm) Please don’t – Long Red (2x) – chromosomes (12 cm) tie pieces – Short Blue (2x) – chromosomes (6 cm) together! – Long Blue (2x) – chromosomes (12 cm) – Green (8x) – Spindle Fibers (40 cm) – Purple (2x) – Nuclear Membranes (50 cm) – Yellow (1x) – Cell Membrane (200 cm) • Points – Diagram to hand in – Quiz Stamp… what’s this?

Cell Set Up • Cell Membrane = Yellow yarn • Nuclear membrane = Purple yarn • Spindle Fibers = Green yarn • Chromosomes = Red & Blue yarn – Drop one of each chromosome into nucleus so they are curled up and overlapping. Your cell is ready to divide!