cell cycle Flashcards
what is binary fission
an organism duplicates its genetic material, and then divides into two parts (cytokinesis), with each new organism receiving one copy of DNA.
process of binary fission
DNA replication
Cell elongation
Septum formation
Cell division
mitosis
process of nuclear division in eukaryotic cells that occurs when a parent cell divides to produce two identical daughter cells
stages of mitosis in order
prophase
metaphase
anaphase
telophase
prophase
chromosomes attach to spindle fibres by their centromeres
early:
chromosomes coil and condense
nuclear envelope present
nucleolus evident
late:
chromosomes visible as two chromatids joined by a centromere
nuclear envelope disappears
nucleolus disappears
spindle fibres form
and the centrioles form and migrate to opposite poles of the cell
metaphase
chromatids pulled to equator/metaphase plate
- centriole grow spindle fibres
- spindle fibres attach to the centromere
- chromosomes pulled to equator
anaphase
sister chromatids are pulled to opposite poles of the cell
- spindle fibres contract
- centromere divides
- each half of the cell receives one chromatid from each chromosome
telophase
-chromatids reach poles of the spindle
-chromatids uncoil and become less distinct
nuclear envelope starts to reform
stages of interphase
Gap 1(g1) Synthesis(s) Gap 2(g2)
G1
cell growth
organelle and protein synthesis
S
DNA replication (each of the 46) chromosomes make exact copies of themselves (chromatids)
G2
cell double checks the duplicated chromosomes for error, making any needed repairs
Cytokinesis animal
begins with the membrane and cytoplasm ‘pinching in on itself’, the formation of a cleavage furrow, and the eventual split into two identical daughter cells.
apoptosis
programmed cell death
cytokinesis plant
involves the formation of a cell plate, which separates and grows to eventually split the plant cell into two identical daughter cells
