Chapter 6: Reproduction at the Cellular Level

Vocabulary flashcards covering essential terms and definitions from BIO 100 Chapter 6 on cellular reproduction, including the cell cycle, mitosis stages, and prokaryotic binary fission.

Cell Cycle

Ordered series of events in which a cell grows, replicates its DNA, and divides; consists of Interphase and the Mitotic Phase.

Interphase

Preparatory portion of the cell cycle (≈90%) containing G1, S, and G2 phases where the cell grows and replicates DNA/organelles.

G1 Phase (First Gap)

Sub-phase of Interphase in which the cell grows and gathers nutrients and energy (ATP) needed for DNA synthesis.

S Phase (Synthesis)

Interphase stage where DNA replication produces sister chromatids and centrosomes duplicate.

G2 Phase (Second Gap)

Interphase stage featuring additional growth, organelle duplication, and energy storage in preparation for mitosis.

Mitotic Phase

Portion of the cell cycle (≈10%) that includes mitosis (nuclear division) and cytokinesis (cytoplasmic division).

Mitosis

Eukaryotic nuclear division producing two genetically identical nuclei; proceeds through Prophase, Prometaphase, Metaphase, Anaphase, and Telophase.

Prophase

First mitosis stage; chromosomes condense, nuclear envelope breaks down, nucleolus disappears, and mitotic spindle forms from centrosomes.

Prometaphase

Mitosis stage where kinetochores form at centromeres and spindle fibers attach to chromosomes.

Metaphase

Mitosis stage in which chromosomes line up at the cell's equatorial plane ("middle").

Anaphase

Mitosis stage where sister chromatids separate and are pulled to opposite poles ("apart").

Telophase

Final mitosis stage; chromosomes reach poles, new nuclear envelopes form, and the spindle disassembles ("two nuclei").

Cytokinesis

Division of the cytoplasm that produces two separate daughter cells, typically overlapping with telophase.

Cleavage Furrow

Contractile indentation of the plasma membrane that pinches animal cells in two during cytokinesis.

Chromosome

DNA-protein structure carrying genetic information; humans possess 46 chromosomes (23 pairs).

Diploid

Condition of having two sets of chromosomes (2n), one set from each parent; characteristic of human somatic cells.

Sister Chromatids

Identical DNA copies of a chromosome produced during S phase and joined at a centromere.

Centromere

Constricted region joining sister chromatids where kinetochores assemble.

Kinetochores

Protein complexes on centromeres that attach chromosomes to spindle microtubules.

Centrosome

Microtubule-organizing center that duplicates in S phase and forms the poles of the mitotic spindle.

Mitotic Spindle

Network of microtubules originating from centrosomes that moves chromosomes during mitosis.

DNA Replication

Process of copying the cell’s DNA during S phase to create identical sister chromatids.

Binary Fission

Simpler asexual division of prokaryotes involving replication of a single circular chromosome, elongation, and cell splitting.

FtsZ Protein

Bacterial protein that forms a contractile ring guiding septum formation during binary fission.

Septum

New cell wall that forms during binary fission, separating two prokaryotic daughter cells.

PPMAT Acronym

Mnemonic—Prophase, Prometaphase, Metaphase, Anaphase, Telophase—for remembering mitosis stages.