AP Bio 4.5 Regulation of Cell Cycle
38 flashcards covering AP Bio 4.5 Regulation of Cell Cycle for the AP-BIOLOGY Unit 4 section.
The regulation of the cell cycle is a critical topic in AP Biology, defined by the College Board as part of Unit 4. This topic explores the mechanisms that control cell division, including checkpoints, cyclins, and cyclin-dependent kinases. Understanding these regulatory processes is essential for grasping how cells grow, replicate, and respond to signals, which is foundational in both biology and medicine.
In practice exams and competency assessments, questions on this topic often focus on the roles of specific proteins and the consequences of their malfunction, such as cancer development. Common question styles include multiple-choice scenarios that require identifying the correct regulatory pathway or explaining the impact of mutations on cell cycle progression. A frequent pitfall is overlooking the distinction between different checkpoints and their specific functions, which can lead to confusion in answering related questions.
One practical tip is to pay close attention to how external signals, such as growth factors, influence the cell cycle, as this aspect is often underestimated in exam preparation.
Terms (38)
- 01
What is the role of cyclins in the cell cycle?
Cyclins are proteins that regulate the progression of the cell cycle by activating cyclin-dependent kinases (CDKs), which phosphorylate target proteins to drive the cell through different phases of the cycle (College Board AP CED).
- 02
How do CDKs function in cell cycle regulation?
Cyclin-dependent kinases (CDKs) are enzymes that, when activated by binding to cyclins, phosphorylate specific substrates to promote cell cycle progression (College Board AP CED).
- 03
What is the significance of checkpoints in the cell cycle?
Checkpoints are regulatory mechanisms that ensure the proper progression of the cell cycle by assessing whether the cell is ready to proceed to the next phase, preventing errors such as DNA damage (College Board AP CED).
- 04
When does the G1 checkpoint occur in the cell cycle?
The G1 checkpoint occurs at the end of the G1 phase, before the cell enters the S phase, and assesses cell size, DNA integrity, and nutrient availability (College Board AP CED).
- 05
What is the function of the p53 protein in the cell cycle?
The p53 protein acts as a tumor suppressor that regulates the cell cycle and prevents the proliferation of cells with damaged DNA by inducing cell cycle arrest or apoptosis (College Board AP CED).
- 06
What happens during the S phase of the cell cycle?
During the S phase, DNA replication occurs, resulting in the duplication of chromosomes, preparing the cell for mitosis (College Board AP CED).
- 07
What triggers the transition from metaphase to anaphase in mitosis?
The transition from metaphase to anaphase is triggered by the activation of the anaphase-promoting complex (APC), which leads to the degradation of proteins that hold sister chromatids together (College Board AP CED).
- 08
What is the role of the spindle assembly checkpoint?
The spindle assembly checkpoint ensures that all chromosomes are properly attached to the spindle apparatus before allowing the cell to proceed to anaphase, preventing chromosome missegregation (College Board AP CED).
- 09
How does the cell cycle respond to DNA damage?
In response to DNA damage, the cell cycle can be halted at checkpoints, allowing for repair mechanisms to fix the damage before the cell continues to divide (College Board AP CED).
- 10
What is the role of growth factors in cell cycle regulation?
Growth factors are signaling molecules that stimulate cell division by promoting the expression of cyclins and other proteins necessary for cell cycle progression (College Board AP CED).
- 11
What is the consequence of uncontrolled cell cycle progression?
Uncontrolled cell cycle progression can lead to cancer, characterized by excessive cell division and the formation of tumors due to mutations in regulatory genes (College Board AP CED).
- 12
Which phase of the cell cycle is characterized by cell growth and preparation for DNA replication?
The G1 phase is characterized by cell growth, synthesis of proteins, and preparation for DNA replication, occurring before the S phase (College Board AP CED).
- 13
What is the role of checkpoints in preventing cancer?
Checkpoints function to monitor and regulate the cell cycle, preventing the division of damaged or abnormal cells, thereby reducing the risk of cancer development (College Board AP CED).
- 14
What is the function of the anaphase-promoting complex (APC)?
The anaphase-promoting complex (APC) triggers the transition from metaphase to anaphase by marking proteins for degradation, ensuring proper chromosome separation (College Board AP CED).
- 15
When do cells enter the G0 phase?
Cells enter the G0 phase when they exit the cell cycle temporarily or permanently, often due to lack of growth factors or when they have differentiated (College Board AP CED).
- 16
What is the significance of the M phase in the cell cycle?
The M phase is significant as it encompasses mitosis and cytokinesis, where the cell divides its replicated DNA and cytoplasm into two daughter cells (College Board AP CED).
- 17
How does apoptosis relate to the cell cycle?
Apoptosis is a programmed cell death mechanism that can be triggered by cell cycle checkpoints in response to severe DNA damage, preventing the propagation of damaged cells (College Board AP CED).
- 18
What is the role of retinoblastoma (Rb) protein in cell cycle regulation?
The retinoblastoma (Rb) protein regulates the cell cycle by inhibiting progression from the G1 phase to the S phase, preventing uncontrolled cell division (College Board AP CED).
- 19
How often must cells undergo the cell cycle?
Cells must undergo the cell cycle regularly, with the frequency varying by cell type; for example, skin cells divide frequently, while nerve cells may not divide at all (College Board AP CED).
- 20
What is the primary purpose of the G2 checkpoint?
The primary purpose of the G2 checkpoint is to ensure that DNA has been accurately replicated and that the cell is ready to enter mitosis (College Board AP CED).
- 21
What can happen if the cell cycle is not properly regulated?
If the cell cycle is not properly regulated, it can lead to uncontrolled cell growth, resulting in cancer or other diseases (College Board AP CED).
- 22
What is the function of telomeres in relation to the cell cycle?
Telomeres protect the ends of chromosomes from deterioration and play a role in limiting the number of times a cell can divide, contributing to cellular aging (College Board AP CED).
- 23
What is the role of mitotic spindle in cell division?
The mitotic spindle is responsible for separating sister chromatids during mitosis, ensuring that each daughter cell receives an identical set of chromosomes (College Board AP CED).
- 24
What occurs during cytokinesis?
During cytokinesis, the cytoplasm of a parental cell is divided into two daughter cells, completing the cell division process after mitosis (College Board AP CED).
- 25
What is the role of checkpoints in the G1 phase?
Checkpoints in the G1 phase assess cell size, DNA integrity, and nutrient availability to determine if the cell can proceed to the S phase (College Board AP CED).
- 26
What happens during the G2 phase of the cell cycle?
During the G2 phase, the cell continues to grow and prepares for mitosis by synthesizing proteins and organelles necessary for cell division (College Board AP CED).
- 27
What is the relationship between the cell cycle and cancer?
The relationship between the cell cycle and cancer involves mutations in genes that regulate the cell cycle, leading to uncontrolled cell proliferation and tumor formation (College Board AP CED).
- 28
What triggers the activation of cyclin-dependent kinases (CDKs)?
The activation of cyclin-dependent kinases (CDKs) is triggered by the binding of specific cyclins, which leads to phosphorylation of target proteins (College Board AP CED).
- 29
What is the outcome of a malfunctioning spindle assembly checkpoint?
A malfunctioning spindle assembly checkpoint can result in aneuploidy, where daughter cells receive an incorrect number of chromosomes, potentially leading to cancer (College Board AP CED).
- 30
What is the role of the G1/S checkpoint?
The G1/S checkpoint assesses whether the cell has adequate resources and undamaged DNA before allowing progression into the S phase for DNA replication (College Board AP CED).
- 31
How does the cell cycle regulate cell differentiation?
The cell cycle regulates cell differentiation by controlling the timing of cell division and the expression of specific genes that lead to specialized cell functions (College Board AP CED).
- 32
What is the significance of the G0 phase in the cell cycle?
The G0 phase is significant as it represents a state where cells are metabolically active but not actively dividing, allowing for differentiation or quiescence (College Board AP CED).
- 33
What is the function of the p21 protein in cell cycle regulation?
The p21 protein functions as a cyclin-dependent kinase inhibitor, blocking CDK activity and thus halting the cell cycle in response to DNA damage (College Board AP CED).
- 34
What happens if a cell fails to pass the G1 checkpoint?
If a cell fails to pass the G1 checkpoint, it may enter the G0 phase or undergo apoptosis to prevent the propagation of damaged or unfit cells (College Board AP CED).
- 35
What is the role of growth factors in stimulating cell cycle progression?
Growth factors bind to receptors on the cell surface, triggering signaling pathways that promote the expression of cyclins and other proteins necessary for cell cycle progression (College Board AP CED).
- 36
What is the impact of mutations in proto-oncogenes on the cell cycle?
Mutations in proto-oncogenes can lead to their conversion into oncogenes, resulting in the promotion of uncontrolled cell division and cancer (College Board AP CED).
- 37
What is the relationship between the cell cycle and apoptosis?
The relationship between the cell cycle and apoptosis involves checkpoints that can initiate programmed cell death in response to irreparable DNA damage, preventing tumorigenesis (College Board AP CED).
- 38
What is the role of the ATM protein in the cell cycle?
The ATM protein is involved in detecting DNA damage and activating signaling pathways that lead to cell cycle arrest and DNA repair (College Board AP CED).