Chapter 8: Cellular Reproduction

Vocabulary flashcards generated from lecture notes covering cellular reproduction, interphase, cytokinesis, cell cycle control, checkpoints, and cancer characteristics.

Cellular Reproduction

A biological process that allows growth and tissue repair in multicellular organisms starting from a single-celled zygote, as well as binary fission in single-celled organisms.

Growth (Cellular Process)

The phase of cellular reproduction where a parent cell doubles its contents.

Cell Division

The phase of cellular reproduction where a parent cell splits its contents between two daughter cells.

Histones

Proteins around which non-dividing DNA winds to form nucleosomes.

Nucleosomes

Structures formed by non-dividing DNA winding around histones, which arrange in a zig-zag pattern to form chromatin.

Sister Chromatids

Two identical copies formed by chromatin condensing before division, joined together at a centromere.

$G_1$ Phase

The interphase stage in which the cell doubles its organelles and accumulates materials needed for DNA replication.

$S$ Phase

The interphase stage during which DNA replication takes place.

$G_2$ Phase

The interphase stage in which the cell synthesizes proteins required for division.

Cleavage Furrow

A furrowing process created by actin filaments in animal cells to divide the cytoplasm during cytokinesis.

Cell Plate

A structure that forms at the equator in dividing plant cells during cytokinesis, giving rise to a new plasma membrane and cell wall.

$G_1$ Checkpoint

A cell cycle checkpoint that assesses cell state; passing it commits the cell to division, whereas damaged DNA beyond repair causes the cell to enter $G_0$ or undergo apoptosis.

$G_2$ Checkpoint

A cell cycle checkpoint that verifies proper DNA replication.

$M$ Checkpoint

A cell cycle checkpoint that ensures proper chromosome alignment before partitioning.

Internal Signals

Molecules such as cyclins and kinases that promote progression through DNA replication and mitosis.

External Signals

Growth factors and hormones that promote cell division, or contact inhibition which halts division.

Telomeres

Structures at chromosome ends that shorten with each division, eventually stopping the cell cycle to prevent instability.

Apoptosis

Programmed cell death occurring via enzymatic destruction of the nucleus and cell structures.

Proto-oncogenes

Genes that normally promote the cell cycle and inhibit apoptosis; gain-of-function mutations turn them into oncogenes that cause uncontrolled cell growth.

Tumor Suppressor Genes

Genes that normally suppress the cell cycle and promote apoptosis; loss-of-function mutations cause a loss of the braking mechanism.

Telomerase Activation

A genetic factor in cancer that keeps telomeres from shortening, enabling unlimited cell division.

Translocations

Chromosomal rearrangements that disrupt regulatory genes.

BRCA1 and BRCA2

Genes associated with inherited mutations that predispose individuals to breast cancer.

RB Gene

A gene associated with an inherited mutation that predisposes individuals to eye tumors.

RET Gene

A gene associated with an inherited mutation that predisposes individuals to thyroid cancer.

Carcinogenesis

The gradual development of cancer resulting from lost cell cycle control.

Angiogenesis

The growth of new blood vessels into a tumor to supply nutrients.

Metastasis

The process by which cancer cells travel through body fluids to form secondary tumors elsewhere.