Reproduction Flashcards
(70 cards)
Name the 5 stages of the cell cycle.
- G1 stage (Presynthetic stage)
- S stage (Syntheis of DNA)
- G2 stage (Postsynthetic stage)
- M stage (Mitosis)
- G0 stage
What occurs during the G1 stage (Presynthetic stage) of the cell cycle?
Cells create organelles for energy and protein production, while increasing their size.
What occurs during the S stage (Synthesis of DNA) of the cell cycle?
Replication of DNA. Strands of DNA, termed chromatin, are held together at the centromere.
What occurs during the G2 stage (Postsynthetic stage) of the cell cycle?
Further cell growth and replication of organelles in preparation for mitosis.
What occurs during the M stage (Mitosis) of the cell cycle?
Mitosis and cytokinesis.
What occurs during the G0 stage of the cell cycle?
The cell is simply living and serving its function without and preparation for division.
The first 3 stages (G1, S, and G2) are known collectively as?
Interphase
Interphase includes what 3 stages of the cell cycle?
- G1 stage (Presynthetic stage)
- S stage (Synthesis of DNA)
- G2 stage (Postsynthetic stage)
Define cytokinesis.
The separation of the cytoplasm and organelles so that each daughter cell has sufficient supplies to survive on its own.
What protein plays a major role in the G1/S and G2/M checkpoints?
p53
What is the purpose of the G1/S checkpoint?
The cell determines if the DNA is in good enough condition for synthesis.
What is the purpose of the G2/M checkpoint?
The cell is concerned with ensuring the cell has achieved adequate size and the organelles have been properly replicated to support two daughter cells.
What are the 2 molecules responsible for the cell cycle?
Cyclin and Cyclin-dependent kinases (CDK)
Note: Cyclins bind to cyclin-dependent kinases activating the CDK-cyclin complex.
Define cyclin-dependent kinases.
Group of protein kinases that are activated by the formation of a complex with a cyclin and are involved in the regulation of the cell cycle.
Name the 2 types of cyclin-dependent kinases (CDK).
- Serine
2. Threonine
Define cyclins.
Any number of proteins associated with the cell cycle of cell division that are thought to initiate certain processes of mitosis.
What is the difference between a chromatin, chromosome, and chromatid?
Chromatin: chromosomes in the form of long thin strands during interphase of the cell cycle.
Chromosome: chromatin condensed during cell division
Chromatid: single replicated chromosome becoming two sister chromatids
Name the 4 G1/S cyclins.
- Cyclin A/CDK2 (active in S phase)
- Cyclin D/CDK4 (regulate G1 to S transition)
- Cyclin D/CDK6 (regulate G1 to S transition)
- Cyclin E/CDK2 (regulate G1 to S transition)
Name the G2/M cyclin(s).
Cyclin B/CDK1 (regulates progression from G2 to M phase)
Name the 4 phases of mitosis.
- Prophase
- Metaphase
- Anaphase
- Telophase
Mnemonic: PMAT
Mitosis production results in what?
2 genetically identical diploid daughter cells from a single cell.
Note: occurs in somatic cells
Diploid cells have how many copies of chromosomes?
2
Haploid cells have how many copies of chromosomes?
1
What happens during prophase of mitosis?
Chromosomes condense, nuclear membrane dissolves, nucleoli disappear, centrioles migrate to opposite sides of the cell, and the spindle apparatus apparatus begins to form.
Note: there are 2 chromosomes during prophase