Section 2 Cells- Topic 3.7 Mitosis

Interphase (Mitosis)

-considerable cell activity
-DNA replicates & cell increases in mass
-Copies of DNA remain joined at centromere

Centromere

Area where the chromatids of a chromosome are attached

Prophase (mitosis)

-Chromosomes become visible
-Centrioles move towards opposite cell poles
-Spindle apparatus forms
-Nucleolus disappears & Nuclear envelope breaks down
-Chromosomes free in cytoplasm brought to cell equator by spindle fibres

Centrioles

Cell organelle that aids in cell division in animal cells only, produces spindle fibres

Spindle apparatus

moves and organizes the chromosomes before cell division

Metaphase

-Chromosomes seen to be made up of two daughter chromatids
-Microtubules attach to centromere in-between chromatids and are pulled along spindle fibres to cell equator

Anaphase

-Centromeres divide and sister chromatids become chromosomes as their pulled to opposite cell poles
-Mitochondria around spindle fibres release energy for chromosome movement

Telephase

-Chromosomes reach respective poles & become longer and thinner before disappearing
-Spindle fibres disintegrate & nucleolus + nuclear envelope reform
-Cytoplasm divides by cytokinesis

Cytokinesis

division of the cytoplasm to form two separate daughter cells