Growth and Division of the Cell
Concepts
Growth Phase of the Cell Cycle
Division Phase of the Cell Cycle
Less common Types of Division
Cell Division in Algae
Cell Division of Prokaryotes #
Division of Mitochondria and Chloroplasts
Cell Cycle
Initiation
Growth
Death
Cell Cycle Arrest
Division stopped
Interphase #
S Phase
G2 Phase
G1 Phase
Temperature
Effects Length of Cycle
longest part of Cell Cycle
Cell Grows
Synthesizes
Enzymes
Nutrients
Entire Chromosomes Replicated
Endoreduplication
Gene Amplification
Cells Prepare for Division
Lasts 3-5 hours
Alpha and Beta tubulins Synthesized
Proteins Produced
Karyokinesis
Mitosis #
Division of Nucleus
Cytokinesis
Prophase
Chromosomes Condense
Nucleolus Breaks Down
Centrioles Migrate to opposite poles
Metaphase
Spindles attach to Centromeres
Chromosomes Move to Center
Metaphase Plate
Anaphase
Sister Chromatids separate
Daughter Chromosomes Move
Opposite Poles
Telophase
Nuclear Envelope Forms
Spindles Depolymerize
Chromosomes Decondense
Cleavage Furrow
Meiosis 1
Two Gametes Fuse Together
Zygote
Prophase 1
Meiosis 2
Leptonene
Zygotene
Pachytene
Diplotene
Diakinese
Metaphase 1
Similar to Mitosis Metaphase
Anaphase
Telophase 1
Interkinesis
Prophase 2
Not Sub-divided like prophase 1
Metaphase 2
Anaphase 2
Telophase 2
Cohesin not Digested
Karyokinesis Occurring without Cytokinesis
Multinucleate Cells Formed
Many Algae Cells are like this
Coenocyte
Thousands of Nuclei
Cell Division Occuring without Nuclear Division
Common in
Algae
Fungi
Nutritive Seed Tissue
Mitosis without Cytokinesis
2 Rounds of Mitosis
Tetranucleate Cells
3 Nuclei on one side
1 Nuclei on the other
Two Large Triploid Nuclei
Two Small Haploid Nuclei
Nulcei
Cytokinesis
Virtually Identical to Animals Nuclei
Dinoflagellites
No Histones
Many Fungal Species Have
Extranuclear Spindle
Intranuclear Spindles
Have no Cell Wall
Plasma Membrane Pinches in
Similar to Animals
Have Cell wall
Similar to Plants
Cell plate Forms
Green Algae
Grows outward
Phycoplast
Red Algae
Phragmoplast
Mitosis does not occur
Meiosis does not occur
Cytokinesis is simpler
DNA
No Protective Histones
Not held by Centromere
DNA Loops Attached to Cell Membrane
Pulled apart as membrane grows
Occurs by Infurrowing
Cell Cycle Short
Around 20min
Several species
Can last days or weeks
Constructed Similar to Prokaryotes
Contains
Circles of Naked DNA
Separated by Membrane Growth
Division Accomplished by
Infurrowing
Being pulled in two
During Cytokinesis
Must receive one mitochondria
Must receive one Plastid
DNA replication is episodic
Division of Cytoplasm
Mitosis is duplication division for growth of the organism. Meiosis is reduction division that occurs in sexual reproduction.
Although Eukaryotes and Prokaryotes divide differently, they both commonly use Cytokinesis.
After Interphase occurs, the next step in the cell cycle is Prophase