2.3 Mitosis

Warm-up Essential Question What is DNA? What is it’s role in the body? Why do cells divide and what are the steps to division?

New vocabulary chromosomes – made up of DNA tightly coiled into a manageable package chromatids – replicated chromosomes- “sister” chromatids that are copies centromeres – where sister chromatids are connected

Why do cells grow? Do they have to divide? Cells are limited in size because the outside (the cell membrane) must transport the food and oxygen to the parts inside As a cell gets bigger, the outside is unable to keep up with the inside, because the inside grows a faster rate than the outside It’s about surface area to volume! When they get to big to support the inside, they divide into two cells

The Cell Cycle The stages in which a cell goes through in order to divide Divided into 4 phases: G1( normal growth), S ( replicate DNA), G2 ( protein synthesis), M ( mitosis) /Cytokinesis

Interphase G1, S, and G2 The “in-between phase” Cell is growing and developing Copies DNA Prepares for division (mitosis) Makes Centrioles (used in Mitosis)

Mitosis part of eukaryotic cell division during which the cell nucleus divides divided into 4 parts Prophase Metaphase Anaphase Telophase

Prophase “preparation” phase – getting ready to divide chromatin condenses into chromosomes centrioles separate, spindles begin to form nuclear membrane breaks down

Metaphase “middle phase” chromosomes line up in the middle of the cell spindle fibers connect chromatids to centromere no nuclear membrane

Anaphase “apart phase” The spindles pull the sister chromatids apart towards opposite sides

Telophase chromosomes gather at opposite ends chromosomes lose distinct shape (unravels) Two new nuclear envelope reforms

Cytokinesis division of cytoplasm into two new daughter cells cytoplasm pinches in half each new cell has identical set of duplicate chromosomes

I(PMAT)C I Picked My Apples Today Carefully I Passed My Anatomy Test Calmly I Prefer Milk And Tea, Carrie

Warm-up Write 3 level 1, 2 level 2 and 1 level 3 questions about the cell cycle.

Write a summary of the cell cycle Your summary should answer the essential question!