Cell DivisionChapter 10

10.1 Cell Growth, Division, and ReproductionKey Questions:

What are some of the difficulties a cell faces as it increases in size?

How do asexual and sexual reproduction compare?

VocabCell divisionSexual reproductionAsexual reproduction

What are some of the difficulties a cell faces as it increases in size?

1. Information overloadAll critical info is stored in DNAAs the cell grows, that info is used build the

molecules neededAs the cell increases, the amount of DNA does

not!If the cell continues to grow there will be a

lack of information

Limit to cell size (continued..)1. Exchanging materials:

The cell needs food, O2, water and other “goods”

The cell must get rid of wastesThese pass through the membrane

Facts to remember:The rate of the “exchange” = surface area

area= L x WThe rate that food and O2 are used =

VolumeVolume = L x W x H

“Surface to Volume Ratio”

How do sexual and asexual reproduction compare?Asexual reproduction:

The production of a genetically identical offspring form a single parent

simpleefficienteffective

Examples of Asexual reproduction

Sexual reproduction-Offspring produced by sexual

reproduction inherit some of their genetic information from each parent.

Asexual vs. Sexual reproductionAsexual:

“survival” tacticQuicker you multiply the better you last!Genetically identity works as long as the

environment stays the sameSexual:

Takes longerGenetic diversity Diversity increased ability to survive in

changing environment

10.2 The process of Cell Division

Key questions:-What is the role of chromosomes in cell

division?

- What are the main events of the Cell Cycle?

-How do daughter cells split apart after Mitosis?

VocabVocab:

ChromosomeChromatinInterphaseCell cycleMitosisCytokinesisProphaseCentromereChromatidCentrioleMetaphaseAnaphaseTelophase

What is the role of Chromosomes in Cell Division?Chromosome:

-genetic information bundled into packages of DNA

What is the role of Chromosomes in Cell Division?Chromosomes help to separate and package DNA precisely during dell division

Chromatin:-DNA, histones within the nucleus

The cell CycleWhat are the main events of the Cell Cycle?

-a cell grows-a cell prepares for division-a cell divides

Prokaryotic Cell Cycle (Binary Fission)

Eukaryotic Cell Cycle

Cell Cycle (continued...)2 main phases:

1. Interphase (in-between)2. Cell Division

Cell CycleInterphase:

G1: cell growthS: DNA replicationG2: preparation for M-phase

M Phase:Mitosis: division of cell nucleusCytokinesis: division of cytoplasm

Mitosisreal life mitosisA GREAT Mitosis VideoProphase

- 1st phase-Takes the longest-50-60% of the time-Genetic material condenses and duplicates-begins spindle forming (centriole)

MitosisMetaphase-2nd phase-nuclear envelope dissolves-chromosomes line up in cell-spindles connect to each centromere

MitosisAnaphase-chromatids separate-move towards opposite side of cell

MitosisTelophase:-final phase -chromosomes untangle-Nuclear envelope re-forms

Cytokenesis

From interphase to cytokinesis

10.3 Regulating Cell cycleKey Questions

How is the cell cycle regulated?How do cancer cells differ from other cells?

VocabCyclinGrowth factorApoptosisCancertumor

How is the cell cycle regulated?Cyclins-discovered 1980’s-protein that seems to regulate cell cycle-start the process

Regulating proteinsInternal Regulators

Control factors within the cell itself

Making sure phases don’t start till one has finished

External Regulatorscontrol of the cell from outside

controls the rate of divisionWound healing is great example

Cell regulation (continued..)Apoptosis:

-Process of programmed cell death.