Chapter 5: The Cell Cycle and Meisois Mitosis Rap

1. What is The Cell Cycle Regular pattern of growth, DNA duplication, and cell division that occurs in eukaryotic cells. Cells: grow prepare for division divide to form two daughter cells begin the cell cycle over again. Cells such as skin, lining of digestive tract and blood cells go through this process frequently Introduction

Life Spans of Body Cells ______________________ Stomach lining cells: 2 days Life Spans of Body Cells ______________________ Platelets: 10 days Skin Cells: 20 days ____________________ Red Blood Cells: 120 days ______________________ ______________________ Brain cells: 30-50 years Intestinal lining cells: 3 days ______________________

Grows & Gets ready to divide 2. The Cell Cycle Grows & Gets ready to divide Cell Grows DNA Replicates

3. Give two reasons why cells need to go through the Cell Cycle As the size of the cell increases, its volume increases faster than its surface area. Surface area to volume ratio would decrease. a. Transport of gases, nutrients and wastes becomes slow b. Difficult for DNA to do its job of directing the production of proteins

4. What is a chromosome? Chromosomes are actually long continuous strands of DNA coiled up on proteins spools that contain numerous genes We have 46 chromosomes in each body cell If cells were the size of a basketball, your DNA would stretch 40 miles We have 6 feet of DNA in each cell!!!!!

Chromatid Protein spools Sister Chromatids

5. What are the functions of: Centrioles (animal cells only) – Perpendicular bundles of microtubules involved in cell division Protein histones/spools – protein structures which DNA will shorted up onto Chromatin – Loose DNA and proteins inside the nucleus Spindle fibers – Protein fibers that attach onto the centromeres of the Sister Chromatids

6. Label the structures on the Paired Chromosomes/Sister Chromatids

Interphase Cell copies its DNA, grows and prepares to divide. DNA is loose and therefore not visible

Prophase DNA coils to become Chromosomes pair up Centrioles (if animal cell) migrate to poles Nuclear envelope & nucleolus start to break down Fibers form

Nuclear Membrane & Nucleolus Form & grow towards centromeres PROPHASE Sister Chromatids Nuclear Membrane & Nucleolus Centrioles Fibers Move to the poles Form & grow towards centromeres Pair up together Begins to break down

Metaphase Sister Chromatids line up on the equator (middle)

Go from the poles to centromeres At opposite ends of cells METAPHASE Sister Chromatids Nuclear Membrane Centrioles Fibers Line up in the middle Go from the poles to centromeres Remains dissolved At opposite ends of cells

Anaphase – “An away they go!” Chromatids separate Go to opposite poles. Now called chromosomes!! Fibers shorten up

ANAPHASE Sister Chromatids Nuclear Membrane Centrioles Fibers Get pulled apart by fibers. Now called a chromosome Still at cell’s poles Remains dissolved Pull chromosomes toward opposite ends

Telophase “the end” – Final phase Chromosomes reach opposite ends Cell membrane pinches in or Cell plate forms (if plants) Chromosomes uncoil Nuclear membrane & nucleolus reappear Fibers disappear

TELOPHASE Sister Chromatids Nuclear Membrane & Nucleolus Cell Membrane Fibers Are now separate chromosomes Pinches in, forming two new cells Disappear Reform

Cytokinesis Dividing up of cellular contents. Occurs simultaneously with Telophase Mitosis and Cytokinesis

Cytokinesis Cytokinesis differs in animal and plant cells. In animal cells, the membrane pinches closed and forms a furrow. In plant cells, a cell plate forms.

7. Label the diagrams below

Mitosis animations Try them all! http://www.sumanasinc.com/webcontent/animations/content/mitosis.html cellsalive. John Kryk You tube (really good) Hybrid (love the music) http://www.csuchico.edu/~jbell/Biol207/animations/mitosis.html McGraw Mitosis Rap

8. Matching _____Sister chromatids pair together A. Interphase _____Sister chromatids line up on the equator B. Prophase _____Pinching in of the cell membrane occurs C. Metaphase _____Sister Chromatids separate D. Anaphase _____DNA is replicated E. Telophase _____The cytoplasm is split between the daughter cells F. Cytokinesis _____The two new daughter cells grow _____The nuclear envelope and nucleolus break down _____The nuclear envelope and nucleolus reassemble _____Spindle fibers form and attach to the sister chromatids _____Separate chromosomes move to opposite poles _____DNA starts to coil up on protein spools & shorten up _____Chromatin is found in the nucleus _____Centrioles reach the opposite poles _____Chromosomes uncoil and become chromatin again

9. Identify 3 differences between Plant and Animal Cell Cycles No centrioles in Plant Cells Cell Plate in Plant cells Cleavage Furrow in Animal cells Centrioles

in a Plant Cell

Plant Mitosis

Interphase Metaphase Telophase Prophase Anaphase

Can You Put These Plant Cells In The Correct Sequence Of Mitosis? 4. Anaphase 1. Interphase 3. Metaphase ___________________ ___________________ ___________________ 2. Prophase 5. Telophase 6. Interphase ___________________ ___________________ ___________________

53.What was the point of Mitosis? Results in two identical daughter cells Each cell will have the SAME number of chromosomes as the original cell Each cell will have the SAME function as the original cells

55.What are the stages of Mitosis? IPMAT Interphase G1 – Cell Grows S – DNA Synthesis G2 – Cell grows and gets ready to divide Mitosis – M phase Prophase – Sets up Chromosomes for division Metaphase – Chromosomes in middle Anaphase – Chromosomes separate Telophase – Chromosomes reach poles and form two identical daughter cells Cytokinesis – division of cell contents

56. Phases, put in order and enter key events 3. Metaphase 5. Anaphase 6. Telophase Spindles shorten up to pull chromosomes Sister Chromatids are on the equator Chromosomes at poles Nucleus & nucleolus appear Spindles gone, Cell pinches in 4. Early Anaphase 1. Prophase 2. Later Prophase Fibers go to Centromeres Centrioles move to poles Nuclear envelope breaks down Sister Chromatids separate and are now chromosomes Sister Chromatids Pair Centrioles move to poles Nucleolus disappears