Cell Division Flashcards
Interphase
Period of cell growth and chromosome replication, 90% of life
Sister Chromatids
Two identical parts of the chromosome
Centromere
Holds together sister chromatids
Chromatin
Coiled DNA, chromosomes not visible during interphase
G1
Phase initiates interphase, active growth phase, cell increases in size and synthesizes proteins
S
DNA synthesis
G2
Cell prepares to divide, grows and synthesizes proteins
M Phase
Mitosis and Meiosis
Mitosis
Division, karyokinesis (nuclear division), cell division (cytokinesis)
Prophase
Chromatin condenses, clearly defined chromosomes, nuclear membrane dissolves, centriole pairs separate and move
Metaphase
Centrioles are located at opposite poles, spindle fibers radiate out and attach at the kinetochore, metaphase plate
Anaphase
Separation of sister chromatids, centromeres split, sister chromatids are pulled toward the opposite poles, shortening of the spindle fibers
Telophase
The spindle apparatus disappears, nuclear membrane forms, diploid number remains, chromosomes uncoil
Cytokinesis
Cleavage furrow forms, indents along the equator, cell plates in plants,
Meiosis
Sexual reproduction, production of haploid cells
Ploidy
Amount of chromosomes in a homologous set (humans are diploid)
Prophase 1
Chromatin condenses, spindle apparatus forms, nuclear membrane disappears, and crossing over occurs to create recombinant chromosomes (synapsis -> tetrad -> chiasmata)
Metaphase 1
Homologous pairs (tetrad) align at the equatorial plane and spindle fibers attach
Anaphase 1
Homologous pairs separate and are pulled to opposite poles, disjunction occurs
Telophase 1
Nuclear membrane forms, forming two haploid cells, intermediate daughter cells
Prophase II
Nuclear envelope dissolves, nucleoli disappears, spindle apparatus forms
Metaphase II
Chromosomes line up
Anaphase II
Sister chromatids are separated
Telophase II
Nuclear membrane forms, cytokinesis follows, four haploid daughter cells are formed in total,
