CH6 Flashcards
2 Stages of a cell division
Karyokinesis; nuclear division
Cytokinesis; cytoplasmic division
3 Stages of Interphase
G1
Cells grow
Cell components are produced
Protein used for cell cycle is synthesised
S
Synthesis of DNA
DNA is replicated
Each chromosome multiplies to form sister chromatids
G2
Cells Grow
Cells gather energy & make arrangement for M Phase
Process of mitosis // meiosis 2
Prophase
Nucleolus disappear
Nuclear membrane disintegrate
Spindle fibre started to form
Centrioles move towards opposite poles
Both sister chromatids are joined at centromere
Metaphase
Chromosomes are aligned on the equatorial plane
Spindle fibre maintains the position of chromosomes
Anaphase
Centromere divides into two
Sister chromatids are seperated
Spindle fibre contracts and shorten
Sister chromatid are attracted towards opposite pole cells
Telophase
Chromatids are known as daughter chromosome
Nucleolus are formed again
New nuclear membrane is formed
Spindle fibre dissapear
Process of meiosis 1
Prophase i
Pairing of homologous chromosome through synapsis to form a tetrad
Crossing-over between non sister chromatid takes place that causes change in genetic material of homologous chromosomes
Spindle fibres are formed, nucleolus disappear, nuclear membrane disintegrate
Metaphase I
Homologous chromosomes are arranged on the equatorial plane
One chromosome from each pair of homologous chromosomes is tied to the spindle fibre from one pole cell, and its pair is tied to spindle fibre from opposite pole cell
Anaphase I
Spindle fibre contracts
Each homologous chromosome is seperated from its homologous pair and is attracted to opposite poles
Telophase I
Nucleolus are formed again
Nuclear membrane is formed
Spindle fibre disappear
Cytokinesis of animal cell
Plasma membrane constricts
Cleavage furrow is formed
Cell seperates into 2 daughter cells
Cytokinesis of plant cells
Start with formation of cell plate at the centre of the cell
Cell plates formed due to fusion of vesicles formed from golgi apparatus
Cell plates grow outwards until it fuses with plasma membrane
New cell wall is formed
Cell seperates into 2 daughter cells
