Karyokinesis
genetic material (chromosomes) is partitioned to daughter cells during nuclear division in mitosis
cytokinesis
cytoplasmic division occurring after karyokinesis
Cell cycle is composed of _________ and _________ (2 words)
interphase, mitosis
Interphase includes:
1. S-phase: during which DNA is synthesized
2. Two gap phases (G1 and G2)
G0
point in the G1 phase where cells withdraw from cell cycle and are non-dividing but still metabolically active.
Mitosis has discrete stages:
1. Prophase
2. Prometaphase
3. Metaphase
4. Anaphase
5. Telophase
Prophase
centrioles divide and move apart
nuclear envelop breaks down
chromosomes condense and become visible
sister chromatids are connected at the ____________
centromere
prometaphase
chromosomes move to equatorial plane of the cell
metaphase
centromeres/chromosomes align at the equatorial plane
_______________ responsible for chromosome movement
spindle fibers bound to kinetochores associated with centromeres
Anaphase
Sister chromatids separate from each other and migrate to opposite poles
the separated sister chromatids are called daughter chromosomes
separated sister chromatids in anaphase are called _________________
daughter chromosomes
Telophase
cytokinesis
uncoiling (relaxation) of chromosomes
re-formation of the nuclear envelope
spindles disappear
Cell cycle Check points
1. G1/S
2. G2/M
3. M check-point
cyclin-dependent kinases
1. G1/S (why is the "/S" here?)*****
monitors cell size
evaluates condition of the DNA
cells enlarge in size
make proteins/enzymes to prepare for S-phase
S
DNA synthesis/replication
2. G2/M
DNA checked for completion of replication/presence of DNA damage
3. M check-point
formation of spindle fibers
attachment of spindles to kinetochores
after pro-metaphase, before metaphase
mitosis is a __ hr process
16hr. 1 hour in mitosis. 15 in interphase
cytokinesis
occurs in telophase
no guarantee cell is divided equally. one cell gets more cytoplasm/organelles
cell plate forms and divides 2 daughter cells
CDK
controls MPF (mitosis promoting factor) at G2/M check point
needs to be enough MPF for Mitosis to begin
___________ is defective in B cell lymphoma
Cycline D