Cell Division and Mitosis Review

A set of flashcards to help review and prepare for the exam on cell division and mitosis.

What are the purposes of cell division in unicellular and multicellular organisms?

In unicellular organisms, cell division serves the purpose of reproduction. In multicellular organisms, it is used for growth, repair, and maintenance.

What are the phases of interphase?

G1 (growth and protein synthesis), S (DNA synthesis and replication), G2 (preparation for mitosis), and Go (stopping point where cells remain metabolically active but do not divide).

What happens during the M-Phase of the cell cycle?

Mitosis occurs, which is the nuclear division, followed by cytokinesis, which is the splitting of the cytoplasm.

How does DNA replication work?

A single-stranded chromosome is turned into a double-stranded chromosome with DNA polymerase adding nucleotides in one direction, and DNA ligase repairing any broken strands.

What is a chromatid?

One half of a replicated chromosome.

What is the role of the centromere?

Holds two chromatids together.

What occurs during prophase of mitosis?

The nuclear membrane breaks down, the nucleolus breaks down, chromatin changes to chromosomes, and spindle fibers and asters form.

What happens during metaphase?

Chromosomes (chromatids) line up at the equator of the cell.

Describe anaphase. What occurs?

Sister chromatids separate and move to opposite poles of the cell.

What changes occur during telophase?

The nuclear membrane and nucleoli re-appear, chromosomes change back to chromatin, spindle fibers and asters disappear, and cytokinesis occurs.

How do animal and plant cells differ in cytokinesis during mitosis?

In animal cells, the cell membrane pinches in to split the cell in half, while in plant cells, a cell plate forms to give rise to the cell wall that splits the cell.

What regulates the progression of the cell cycle?

Cyclins regulate the progression by activating kinases, which are enzymes that add phosphate groups to molecules.

What issues do cancer cells have related to cell division?

Cancer cells have mutations in tumor-suppressor genes and proto-oncogenes, leading to uncontrolled cell division.

What are proto-oncogenes?

Genes that, if mutated, can turn normal cells into cancerous cells.

What should you study to identify stages of mitosis?

Study diagrams of mitosis.