Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 4: Growth and Division of the Cell (Cell Division of Prokaryotes…
Chapter 4: Growth and Division of the Cell
Growth Phase of the Cell Cycle
G1 Phase
Synthesis of Nucleotides
Longest Part of Cell Cycle
Some cells are here for life
G2 Phase
Cells prepare for division
Lasts 3-5 hours
Produces proteins
Division occurs immediately after
S Phase
Genes in the Nucleus are replicated
Entire Chromosomes replicated
Histones complexes with DNA
Provides: Protection and Structure
Endoreduplication
Occurs in 80% of Maturing Plant Cells
Occurs most often in cells with rapid metabolism
Gene Amplification
Only some genes are repeatedly replicated
Arum maculatum
24, 576 copies of every gene
aka Resting Phase
Division Phase of the Cell Cycle
Mitosis
Duplication Division
Nuclear genes are first copied
Prophase
Chromosomes Condense & Coil
Spindle Microtubules attach to Centromeres
Metaphase
Chromosomes move to the Metaphase Plate
Chromatids are freed
Anaphase
Spindle Microtubules pull each chromosome away
Uses 20 ATP Molecules
Telophase
Form complete nuclear envelopes
Chromosomes become less distinct
Produce ribosome subunits
Reversal of Prophase
Cytokinesis
Division of Protoplast
Preprophase Band
Identifies plane of division
Formation of Phragmoplast
Forms in cell center
Cell Plate
Phragmosome
Vacuole Division
Meiosis
Zygote is formed
aka Reduction Division
Meiosis I
Prophase I
Leptotene
Chromosomes begin to condense
Zygotene
Pairing of Chromosomes
Synapsis
Each chromosome pairs with its homolog
Bivalent
Pachytene
Chromosomes become shorter and thicker
Crossing-over
Diplotene
Chromosomes move away from each other
Attached at Chiasmata
Diakinesis
Chromosomes continue to seperate
Metaphase I
Metaphase Plate is formed
Anaphase I
Chromosomes seperate, moving to opposite ends of the Spindle
Each chromosome has 2 chromatids
Telophase I
Opposite of Prohase II
Interkinesis
Chromosomes uncoil
Meiosis II
Prohase II
Opposite of Telophase I
Not divided into stages
Prepares nucleus for division
Metaphase II
Very short
Centromeres divide
Anaphase II
Seperates new chromosomes from replicate
Telophase II
New Nuclei are formed
Less Common Types of Division in Plants
Karyokinesis
Formation of Multinucleate cells
Coenocyte
100s of Nuclei in one cell
Cell division without Nuclear Division
Common in:
Algae
Fungi
Nutritive tissues of seeds
Cell Division in Algae
Nuclei
Plant nucleus identical to animal nucleus
Has both intrnuclear abd extranuclear spindle
Gaps form in nuclear envelope
Dinflagellate nucleus
Has no histones
Cytokinesis
Similar to animal cell cytokinesis
Phycoplast
Microtubules perpendicular to spindle
Cell Division of Prokaryotes
No Mitosis/ Meiosis
No histones
DNA pulled as cell grows
Cytokinesis occurs by infurrowing
Very short process
Division of Chloroplasts and Mitochondria
Similar to prokaryotes
Contain circles of naked DNA
Infurrowing
