Cell Regulation

Which phrase best describes a common characteristic of all cancers?

• absence of cyclins
• damaged DNA
• uncontrolled cell growth
• inherited from parents

What is the role of protein kinases?

• remove phosphate groups to deactivate enzymes

• trigger apoptosis

• add phosphate groups and energy to activate enzymes

• stop the cell cycle

Which description is true about cell cycle regulation?

• Changing concentrations of Cdk result in binding to cyclin
• Changing concentrations of cyclin result in binding to Cdk
• MPF complex formation decreases with increased Cdk levels
• MPF complex formation decreases with increased cyclin levels

Which of the following correctly describes cells that are in the G₀ phase?

• Mature nerve and muscle cells are unable to divide and are permanently in G₀.

• Many cells enter G₀ when they reach the checkpoint during the M phase.

• Cells in G₀ are growing and preparing for cell division.

• DNA replication occurs during G₀.

Which of these is a risk factor for developing cancer? CHECK ALL THAT APPLY

• growing older

• genetic inheritance

• exposure to carcinogens (toxins that can damage DNA)

• smoking

When it occurs at the proper time, programmed cell death (apoptosis)

• will disrupt homeostasis
• may cause defective genetic info to be passed to the next generation of cells
• is an important regulatory process that maintains the health of a multicellular organism
• can contribute to the development of cancer

What kind of a gene is p53?

• Proto-Oncogene
• Oncogene
• Tumor Suppressor Gene
• Proto-Tumor Suppressor Gene

Which of the following is a type of protein that regulates the cell cycle? 

• actin 
• myosin 
• cyclin 
• pepsin 

What is apoptosis?

• A tumor

• A protein

• Programmed cell death

• Cell cycle checkpoints

DNA is replicated during ______ of the cell cycle.

• G1
• S
• G2
• G0