Cellular Reproduction Vocabulary

Flashcards covering key vocabulary and concepts from the Cellular Reproduction lecture notes.

Cell Cycle Checkpoints

G1 checkpoint, G2 checkpoint, Mitotic stage checkpoint

G1 Checkpoint

Significant checkpoint where the cell commits to divide. Can enter G0 if not passed. Checks for proper growth signals and DNA integrity. Apoptosis occurs if DNA repair is not possible.

G2 Checkpoint

Verifies that DNA has been replicated and that any DNA damage has been repaired.

Mitotic Stage Checkpoint

Occurs between metaphase and anaphase. Ensures all chromosomes are attached to the spindle before proceeding.

Signal

A molecule that stimulates or inhibits an event in the cell cycle.

Kinases

Enzymes that remove a phosphate from ATP and add it to other molecules, acting as an on/off switch for cellular activities. Active in removal of nuclear membrane and condensation of the chromosome

Cyclins

Internal signals present only during certain stages of the cell cycle. The proper cyclin molecule must be present at the correct level for the cell to progress. Destruction of cyclin is necessary for normal cell cycle progression.

Epidermal Growth Factor (EGF)

Stimulates skin cells near an injury to finish the cell cycle, repairing damage.

Contact Inhibition

Cells stop dividing when they touch each other.

Telomere

Repeating DNA sequence (TTAGGG) at the end of a chromosome that promotes chromosome stability. Shortens with each cell division, and when it becomes too short, the cell dies via apoptosis.

Apoptosis

Programmed cell death, unleashed by internal or external signals, helps maintain appropriate cell numbers, and is a normal part of growth and development.

Cancer

A disease of the cell cycle in which cellular reproduction occurs repeatedly without end, often due to mutations in genes.

Proto-oncogenes

Genes that code for proteins that stimulate cell division and prevent apoptosis. When mutated, they become oncogenes, causing excessive cell division.

Tumor Suppressor Genes

Genes that code for proteins that inhibit cell division and promote apoptosis. When mutated, they lose their function, allowing uncontrolled cell division.

Telomere Shortening (in cancer)

Absence of telomere shortening can lead to chromosome instability and may be lost.

Translocations

Chromosomal rearrangements where portions of DNA are lost, duplicated, or scrambled. A portion of a chromosome may break off and reattach to another chromosome.

BRCA1 and BRCA2

Genes that produce tumor suppressor proteins that help repair DNA; mutations are associated with breast cancer.

Retinoblastoma (RB) gene

A tumor suppressor gene that produces a protein, pRB (eye tumor).

Metastasis

The process by which cancer cells travel to start new tumors in other parts of the body.

Angiogenesis

The formation of new blood vessels to nourish a tumor.

Benign Tumors

Tumors that are contained within a capsule and do not invade surrounding tissues.

Malignant Tumors

Tumors that are invasive, may spread (metastasize), and may travel through the blood or lymph to start new tumors elsewhere.

Radiation Therapy

A cancer treatment that kills cancer cells by damaging their DNA or interfering with mitosis. Targets cells within a specific tumor.

Chemotherapy

A cancer treatment that kills cancer cells that have spread throughout the body. Damages DNA or some aspect of mitosis.