Warm-Up 11/15/10 LIST the Phases of the Cell Cycle. Which Phase of the CELL CYCLE includes Prophase, Telophase, Anaphase, Metaphase? Put the Above-mentioned Phases in the correct Chronological Order.

Warm-Up 11/16/10 Which organism has larger cells? How does Size & Shape Affect how efficient a Cell is?

Warm-Up 11/16/10 Identify the formula for the following: –Surface Area –Volume What are the metric units associated with each measurement?

Identify the formula for the following: –Surface Area SA of Rectangle = 2(lw + lh + wh) Volume of Rectangle = L x W x H

What are the metric units associated with each measurement? –SA Ex: 2 [(2m x 2m) + (2m X 2m) + (2m x 2m)] = 24m 2 –Volume Ex: 2m x 2m x 2m = 8m 3

What is the ratio of SA to Volume in the following example? –SA Ex: 2 [(2m x 2m) + (2m X 2m) + (2m x 2m)] = 24m 2 –Volume Ex: 2m x 2m x 2m = 8m 3 –SA / Vol = 24m 2 / 8m 3 = 3 / 1

Warm-Up 11/17/10 What is the purpose of the Cell Cycle? What are the Phases of Mitosis in chronological order?

Exit Ticket Identify the differences between the Cell Cycle and Mitosis.

Cell Growth and Reproduction Section 10.2 CSII-H

Limits to cell growth DNA – can only control the needs of a small cell Cell Size - cell must have a low surface to volume ratio Cell Division – when a cell gets too large to control or function efficiently, cell division takes place

Cell Cycle Growth Nuclear division Cytoplasmic division.

Warm-up What are the 4 phases of mitosis? –Prophase –Metaphase –Anaphase –Telophase

Interphase G1 – growth phase –> cell gets bigger and develops. S – synthesis phase –> DNA in nucleus is copied. G2 – growth phase –> more growing and developing; produce more organelles, enzymes, centrioles are replicated, etc.

Mitosis Nuclear division Yields 2 daughter nuclei that are genetically identical. Used for Growth and Healing.

Prophase Chromatin condenses into chromosomes, 2 identical strands of DNA attached by a centromere. Centrioles move to opposite ends of the cell. Nuclear envelope and nucleolus disappear. Spindle starts to appear.

Metaphase Chromosomes line up on Metaphase Plate between the centrioles. Spindle fibers attach to chromosomes at centromeres.

Anaphase Centromeres are pulled apart as spindle fibers contracts. Chromatids (half of a chromosome) are pulled in opposite directions. Chromatids are pulled to opposite ends of the cell.

Telophase Chromatids complete journey to the ends of the cell. Chromatin is formed as DNA elongates. Nuclear envelope forms around each set of DNA. Spindle disappears Nucleoli appear in each nucleus

Cytokinesis Cytoplasmic Division Begins during anaphase Furrow / ring starts to develop in the middle of the cell membrane

Cytokinesis In plants, you start to develop a cell plate Ring contracts until it completely separates the two new nuclei and about ½ organelles into each new cell

Control of the Cell Cycle Cyclins (proteins) regulate cell growth Internal regulators – only move to the next phase of the cell cycle when the previous phase is complete

Control of the Cell Cycle External regulators – if there is room, a cell divides; if neighboring cells are touching, cell growth is inhibited because space is scarce

Cancer Uncontrolled cell growth. Tumors are cells that do not respond to cell regulators. Results from a loss of regulation / control during the cell cycle.

Apoptosis Normal part of development for most cells in a multi- celled organism. Special enzymes will break cells down.