28 Questions
During which phase of the cell cycle is DNA replicated?
S
Where does the 'restriction point' occur in the cell cycle?
G1
In which phase are nerve and muscle cells typically found?
G0
When is the cyclin component of MPF destroyed in the cell cycle?
M
Which phase of the cell cycle is known as the 'Gap 2' phase?
G2
What characteristic is commonly observed in cells from an advanced malignant tumor?
Abnormal chromosomes
Why might cancer cells from an advanced malignant tumor have abnormal chromosomes?
Introduction of new chromosomes through transformation
What is a possible consequence of cancer cells no longer being density dependent?
Increased metastasis
Besides overproliferation, what could lead to the formation of a tumor?
Failure to undergo appropriate cell death
What process might contribute to the abnormal chromosome numbers seen in advanced malignant tumors?
Bypassing cell cycle checkpoints
What could logically result in the inability of chromosomes to properly align at the metaphase plate?
Failure to form functional spindles
What did the research team conclude based on the incorporation of labeled nucleotides into a culture of lymphocytes?
Infection causes lymphocytes to divide more rapidly.
What is the outcome if mammalian cells receive a go-ahead signal at the G1 checkpoint?
Complete the cycle and divide.
What happens to cells that are in a nondividing state?
Switch to a nondividing state.
How does the presence of a pathogen affect the labeled nucleotide incorporation in lymphocytes?
Increases nucleotide incorporation in lymphocytes.
What is the significance of the G1 checkpoint in mammalian cells?
Triggers cell division.
How do infections affect cell cultures according to the text?
Stimulate lymphocytes to divide rapidly.
What is the protein that is synthesized at specific times during the cell cycle and associates with a kinase to form a catalytically active complex?
MPF
Which protein, maintained at constant levels throughout the cell cycle, requires cyclin to become catalytically active?
cyclin
What triggers the cell's passage past the G2 checkpoint into mitosis?
MPF
Which one of the following is NOT a correct match between the protein and its role in the cell cycle?
Cdk - Inhibits cell division
During which phase of the cell cycle is cyclin maintained at constant levels?
G1 phase
What is the main function of spindle microtubules that do not attach to kinetochores?
Maintaining the area where fibers overlap in the cell's center
How can radiolabeled nucleotides be used to track their incorporation into newly forming DNA?
To identify the exact location where DNA synthesis initiates
What is the primary purpose of introducing labeled T nucleotides into a culture of dividing human cells at specific times?
To monitor the incorporation of nucleotides into newly forming DNA
Which aspect of cellular activity is NOT directly related to spindle microtubules during mitosis?
Initiation of DNA replication
Why is it significant to introduce labeled T nucleotides into a culture of dividing human cells when studying DNA synthesis?
To track and analyze how nucleotides are integrated into replicating DNA
In the context of monitoring DNA replication, what information can be obtained by tracking the incorporation of radiolabeled nucleotides?
The timing and duration of specific phases in the cell cycle
Test your knowledge on the cell cycle and cell division with questions about DNA replication, cell cycle phases, and regulatory checkpoints. Explore topics such as cell cycle phases, DNA replication timing, and cell cycle regulation.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
