Cell Cycle and Mitosis Concepts

Front

What is the role of cyclins in the cell cycle?

Back

Cyclins are proteins that regulate the progression of the cell cycle by activating cyclin-dependent kinases (Cdks). They are synthesized and degraded at specific phases of the cell cycle.

Front

What happens to cyclin levels during the M phase of the cell cycle?

Back

Cyclin levels decrease as cyclins are destroyed toward the end of the M phase, leading to the inactivation of cyclin-dependent kinases (Cdks).

Front

What are chromosomes made of in eukaryotic cells?

Back

Chromosomes in eukaryotic cells are composed of DNA and proteins, which together form chromatin.

Front

What is the G0 phase in the cell cycle?

Back

The G0 phase is a resting state where cells exit the cell cycle and do not actively divide. Cells in G0 may remain metabolically active but are not preparing to divide.

Front

Why do neurons divide infrequently?

Back

Neurons and some specialized cells divide infrequently because they have been shunted into the G0 phase, where they exit the cell cycle.

Front

What is the S phase of the cell cycle?

Back

The S phase (synthesis phase) is the part of the cell cycle where DNA is replicated, resulting in the duplication of chromosomes.

Front

How can the length of the S phase be measured experimentally?

Back

The length of the S phase can be measured by using radiolabeled nucleotides and tracking their incorporation into newly synthesized DNA.

Front

What is the significance of cohesin during cell division?

Back

Cohesin is a protein complex that holds sister chromatids together until anaphase, ensuring proper segregation of chromosomes during cell division.

Front

What event marks the beginning of anaphase?

Back

The beginning of anaphase is marked by the enzymatic cleavage of cohesin, allowing sister chromatids to separate.

Front

What is the function of kinetochores?

Back

Kinetochores are protein structures on the chromosome that attach to spindle fibers during cell division, facilitating the movement of chromosomes.