Title: Webstraw: Cell Bio Anki Deck / Section 6 - Cell Cycle

Q: The cell cycle is the ordered sequence of event in which a cell copies its [...] to divide into 2 genetically [...] cells
A: DNA and chromosomes; identical

Q: Interphase includes
1. [...] phase
2. [...] phase
3. [...] phase
A: G1; S; G2

Q: [...] phase describes generalized growth of cells and arrest when not dividing ([...])
A: G1; G_0

Q: [...] phase is the longest phase in the cell cycle
A: G1

Q: [...] phase describes when cells undergo DNA replication
A: S

Q: [...] phase describes when cells prepare for chromosome segregation and cell division
A: G2

Q: M phase describes when the cell undergoes [...]
A: mitosis

Q: cell cycle stages in budding yeast S. cerevisiae can be inferred by size of [...]
A: bud

Q: cell cycle stages in fission yeast S. pombe can be inferred by [...] of rods
A: length

Q: S. cerevisiae and S. pombe both have [...] sensitive mutants that cause defects in proteins required to progress through the cell cycle
A: temperature

Q: loss of cdc2 prevents S. pombe from entering [...]
A: M phase

Q: cdc2 is also known as a [...]
A: CDK (cyclin dependent kinase)

key regulators in the cell cycle
1. kinases - adds phosphate groups
2. phosphatases - removes phosphate groups
3. cyclins - functions to regulate kinases

Q: a heterodimer of CDK and mitotic cyclin forms a [...]
A: MPF (mitosis-promoting factor)

Q: Cdc2 is inactive for most of the cell cycle but peaks as [...] and becomes inactive as [...]
A: M phase begins; M phase ends

Q: Cdc2 activity triggers [...] and amount of Cdc2 is [...] throughout cell cycle
A: G2 to M phase; constant

Q: amount of [...] fluctuates during cell cycle and activity of Cdc2 is regulated by [...]
A: cyclin; cyclin

Q: cyclin levels are regulated by [...]-mediated [...]-dependent degradation
A: ubiquitin; proteasome

Q: [...] binds to cyclin to signal [...] to degrade cyclin
A: ubiquitin; 26S proteasome

Q: [...] are kinases that phosphorylate CDK to inactive it
- excess {{c1:Wee1}} causes increased G2 phase
A: Wee1

Q: [...] is a phosphatase that removes phophate group from CDK to activate CDK
- excess [...] decreases G2 phase
A: Cdc25; Cdc25

Regulation of MPF activity
1. Wee1 phosphorylates CDK at Tyr15 to prevent premature activation
2. CAK phosphorylates CDK at Thr161
3. Cdc25 removes phosphate at Tyr15 to activate CDK when MPF is ready for M phase

Q: MPF should be inactive during [...] phase and [...] phase
A: S; G2

active MPF causes
1. chromosme condensation
2. disassembly of nuclear envelope
3. interphase microtubule disassembly
4. mitotic spindle formation

Q: MPF must be inactivated at [...]
A: anaphase

Q: [...] is a ubiquitin ligase and recognizes 9 amino acid sequence in cyclin to induce degradation by [...]
A: APC/C; proteasomes

Q: S phase entry is regulated by degradation of [...] inhibitor by [...]
A: CDK; SCF ubiquitin ligase

Q: SCF ubiquitin ligase recognizes [...] inhibitor and promotes its destruction to activate S phase [...]
A: phosphorylated; cyclin

the 4 main stages of mitosis are
1. prophase - nuclear envelope breakdown, spindle apparatus formation, chromosomes condensation
2. metaphase - alignment of chromosomes at metaphase plate
3. anaphase - separation of sister chromatids
4. telophase - chromosomes decondense and nuclear envelope reforms

Q: yeast mutants are called [...]
1. [...] in S. pombe
2. [...] in S. cerevisiae
A: cell division cycle mutants (cdc); cdc2; cdc28