10.1 Division Flashcards
What occurs during the G1 phase of the cell cycle?
Cell growth and preparation for DNA replication
G1 is the first gap phase where the cell increases in size and synthesizes proteins necessary for DNA synthesis.
What is the S phase of the cell cycle responsible for?
DNA synthesis and replication
During the S phase, each chromosome is replicated to produce two sister chromatids.
What happens during the G2 phase of the cell cycle?
Preparation for mitosis and further growth
G2 is the second gap phase where the cell continues to grow and produces proteins needed for cell division.
What are stimulatory proteins in the cell cycle?
Growth factors, cyclins, cdks
These proteins promote cell division and progression through the cell cycle.
What is the role of cyclins in the cell cycle?
Regulate the timing of the cell cycle by activating cdks
Cyclins are proteins that fluctuate in concentration and are essential for the progression through different phases of the cell cycle.
What are cdks?
Cyclin-dependent kinases that regulate cell cycle progression
Cdks are enzymes that, when activated by cyclins, phosphorylate target proteins to drive the cycle forward.
What is the function of p53 in the cell cycle?
Inhibitory protein that prevents cell cycle progression in response to DNA damage
p53 is known as the ‘guardian of the genome’ for its role in maintaining genomic stability.
What are proto-oncogenes?
Normal genes that can become oncogenes when mutated
Proto-oncogenes typically promote cell growth and division but can lead to cancer when mutated.
What are tumor suppressor genes?
Genes that inhibit cell division and prevent tumor formation
Tumor suppressor genes, like p53, play a crucial role in regulating cell cycle checkpoints.
