Materials move through cells by diffusion. Oxygen and food move into cells, while waste products move out of cells. How does the size of a cell affect how efficiently materials get to all parts of a cell? 1.On a sheet of paper, make a drawing of a large cell, then make a drawing of a cell (1/2) half the size. 2. Compare your drawings. How much longer do you think it would take to get from the cell membrane to the center of the big cell than from the cell membrane to the center of the smaller cell? 3.What is the advantage of cells being small? It would take twice the amount of time. If cells are small, materials can be distributed to all parts of the cell quickly. Do Now

BIGGER CELLS NEED MORE FOOD and OXYGEN, but CAN’T TRANSPORT IT FAST ENOUGH or IN BIG ENOUGH QUANTITIES!

Image from: Image by Riedell CELL GROWTH & DIVISION 10-1 & 10-2

Multicellular organisms grow mainly by increasing cell number Image from: Image by Riedell

CHROMATIN SPREAD OUT IN NON-DIVIDING CELLS CHROMOSOMES SCRUNCHED UP IN DIVIDING CELLS DNA CAN BE:

Chromosome structure CHOMOTIDS 2 identical arms CENTROMERE constricted area holds chromatids together

HOMOLOGOUS CHROMOSOMES SAME SIZE SAME SHAPE CARRY GENES for the SAME TRAITS

______________ = series of events that cells go through as they grow and develop CELL CYCLE

Go to Section: M phase G 2 phase S phase G 1 phase Figure 10–4 The Cell Cycle Section 10-2

Cell Cycle Worksheet define each component of the cell cycle on the worksheet Textbook: Page 245

Do Now Name the different phases of interphase

Review for chapter 10 test tomorrow

PROPHASE 1st dividing phase DNA scrunches into chromosomes Pearson Education Inc publishing as Pearson Prentice Hall

METAPHASE Chromosomes line up in ___________ middle Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

ANAPHASE Centromeres split Centrioles pull chromatids_______ apart Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

TELOPHASE (reverse prophase steps) See ______ nuclei Nuclear membrane & nucleolus return two Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

CYTOKINESIS Cytoplasm splits into 2 cells CLEAVAGE FURROW

Go to Section: includes is divided into Concept Map Section 10-2 Cell Cycle 12 InterphaseMitosis 31234

Go to Section: includes is divided into Concept Map Section 10-2 Cell Cycle M phase (Mitosis) Interphase G 1 phaseS phaseProphaseG 2 phaseMetaphaseTelophaseAnaphase

Cell Cycle Regulators Cyclin - protein that regulates the cell cycle Cyclins regulate the timing of the cell cycle in eukaryotic cells

Uncontrolled Cell Growth Cancer - disorder where some of the body’s own cells lose the ability to control growth Cancer cells do not respond to the signals that regulate the growth of most cells

Creating the Four Phases of Mitosis MAKE DRAWING OF THE FOUR PHASES OF MITOSIS ( COMPLETE ON LEGAL SIZE PAPER) USE TEXTBOOK PAGE 247 DRAW IN ORDER of: 1.PROPHASE, 2. METAPHASE, 3.ANAPHASE AND 4.TELOPHASE. USE ONLY THE COLORED CHROMOSOMES AS YOUR EXAMPLE OF EACH PHASE LABEL EACH PHASE AND EXPLAIN WHAT OCCURS DURING EACH PHASE

Homework 10-3 Section Assessment Questions 1 to 5 Test on Friday: Chapter 10 Cell Division