Cell Cycle and Mitosis Study Guide

These flashcards cover key concepts and details related to the cell cycle, mitosis, cancer, and related biological processes.

What are the stages of the cell cycle?

G1 phase, S phase, G2 phase, and M phase (mitosis).

What is the main event occurring during the S phase of the cell cycle?

DNA replication, where each chromosome is duplicated.

What is the purpose of the G1 checkpoint?

To check for nutrients, growth factors, and damaged DNA before the cell proceeds to DNA synthesis.

What happens during the G2 phase?

The cell prepares for division by checking chromosome duplication and restoring energy stores.

What occurs during prophase of mitosis?

The nuclear membrane disappears, spindle fibers form, and DNA condenses into visible chromosomes.

What is the role of centrioles in mitosis?

They organize microtubules and help separate chromosomes during cell division.

What is the process of cytokinesis?

The division of the cytoplasm, resulting in two new daughter cells after mitosis.

What are telomeres and their function?

Noncoding regions at the ends of chromosomes that protect coding DNA from degradation.

What is apoptosis?

Pre-programmed cell death that helps eliminate damaged or unnecessary cells.

What characterizes cancer cells?

Altered morphology, loss of contact inhibition, uncontrolled division, and evasion of apoptosis.

What is the role of tumor suppressor genes?

To prevent the formation of tumors by regulating cell growth and division.

What is the relationship between stem cells and telomerase?

Stem cells produce telomerase, allowing them to maintain telomere length and divide indefinitely.

Define neoplasm.

An accumulation of abnormally dividing cells, which can be benign (harmless) or malignant (cancerous).

What is the purpose of checkpoints in the cell cycle?

To ensure cells do not proceed to the next stage if conditions are not favorable or if there is DNA damage.

What happens if the EGFR gene mutates?

It can lead to uncontrolled cell division, even without the presence of its growth factor EGF.

Describe the difference between benign and malignant tumors.

Benign tumors are harmless and do not spread, while malignant tumors can invade surrounding tissues and spread throughout the body.

What is the consequence of telomere shortening?

Cells can enter senescence and stop dividing, which can impact tissue function as the organism ages.

What is mitosis?

The stage of the cell cycle where nuclear division occurs, maintaining chromosome number in daughter cells.

What are the four stages of mitosis?

Prophase, Metaphase, Anaphase, and Telophase.

What is the cleave furrow?

The indentation where cytoplasmic division occurs in animal cells during cytokinesis.

What is a proto-oncogene?

A normal gene that can become an oncogene due to mutations, potentially leading to cancer.

What is cancer?

A disease characterized by uncontrolled cell division that disrupts normal bodily functions.