Cell Division, Mitosis, and Meiosis Review

Vocabulary flashcards covering the stages of mitosis, meiosis, chromosome structure, cell cycle regulation, and related genetics concepts.

Taxol (paclitaxel)

A cancer drug that stabilizes microtubules and prevents their disassembly, arresting dividing cancerous cells during anaphase of mitosis.

Metaphase plate alignment

The lining up of chromosomes during metaphase to ensure they are properly attached to spindle microtubules so that they separate properly during anaphase.

Nucleolus disappearance in prophase

The breakdown of the nucleolus that occurs when chromosomes condense and ribosomal RNA synthesis stops during prophase.

Cyclins

Regulatory proteins that primarily control the progression of the eukaryotic cell cycle.

Interphase

The longest period of the cell cycle, composed of the $G_1$, $S$, and $G_2$ phases, during which DNA replicates, centrioles divide, and proteins are actively produced.

Telophase (mitosis)

The stage of mitosis that is essentially the reverse of prophase, characterized by daughter chromosomes arriving at opposite poles and the nuclear envelope reforming.

Binary fission

The bacterial cell division process in which a single cell divides into two nearly equal halves.

Genome

The complete set of an organism's genes and other DNA sequences.

Roundworm gamete chromosome number

Two ($2$) chromosomes, which is the haploid number found in an ovum given that roundworm somatic cells have four chromosomes.

Mitosis vs. Meiosis I chromosome separation

A major difference where sister chromatids separate during mitosis, whereas homologous pairs of chromosomes separate during meiosis I.

Human X chromosome

A sex chromosome that carries genes influencing an individual's biological sex.

Unicellular haploid stage

A characteristic feature of the sexual life cycle of most fungi that is absent from the sexual life cycles of plants and animals.

Sister chromatids

The two identical copies comprising a single duplicated chromosome.

Parthenogenesis (Komodo dragon)

A form of asexual reproduction that can occasionally occur in organisms such as the Komodo dragon.

Nondisjunction

The failure of chromosomes or chromatids to separate properly during cell division, resulting in gametes with $n+1$ or $n-1$ chromosomes.

Chromosome composition of a normal human male

44 autosomes, 1 X chromosome, and 1 Y chromosome.

Chromosome composition of a normal human female

44 autosomes and 2 X chromosomes.

Consequence of sexual reproduction without meiosis

A doubling of the chromosome number in each successive generation.

Autosomes

Chromosomes that do not determine the biological sex of an individual.

Homologous chromosomes

Chromosome pairs that carry genes controlling the same inherited characteristics.

Turner syndrome

A genetic condition caused by nondisjunction in which a female is born with only one X chromosome, often leading to shorter stature and atypical pubertal development.

Chromatin

The structural material within the eukaryotic nucleus consisting of DNA and protein.

Animal cytokinesis

The physical division of the cytoplasm in animal cells, which typically begins during anaphase and uses a contractile ring of actin to cleave the cell into two daughter cells.

Apoptosis

Programmed cell death initiated when a cell is too old, damaged, or fails a checkpoint during cell cycling.

Anaphase (mitosis)

The stage of mitosis where sister chromatids (daughter chromosomes) are pulled apart and migrate toward opposite cell poles.

S phase

The specific phase of interphase during which each chromosome is duplicated to ensure both daughter cells receive a full copy.

Prophase I (meiosis)

The stage of meiosis during which homologous chromosomes pair up and crossing over occurs to produce recombinant homologous chromosomes.

Metaphase I (meiosis)

The stage of meiosis during which recombinant homologous chromosome pairs align at the equatorial plate.

Metaphase II (meiosis)

The stage of meiosis during which separate recombinant chromosomes align at the equatorial plate and spindle fibers attach to each sister chromatid.