Cell Division Flashcards

Vocabulary flashcards for cell division lecture review.

Cell Division

Nuclear division followed by cytoplasmic division.

Homologous Chromosomes

Two copies of every chromosome in diploid cells, forming pairs.

Centrosomes

Cellular structures in animal cells that contain a pair of centrioles and produce spindle fibers.

Centrioles

Produce spindle fibers that separate sister chromatids during anaphase.

Cell Cycle

Phase of the cell cycle divided into G1, S, and G2, and the Mitotic phase (mitosis and cytokinesis).

G1 Phase

Phase where the cell increases in size and ensures everything is ready for DNA synthesis.

S Phase

Phase where DNA is replicated, creating sister chromatids.

G2 Phase

Phase where rapid cell growth continues and genetic material prepares for cellular division.

G0 Phase

Inactive state of cells not actively growing or dividing.

Spindle Apparatus

Forms during prophase and is crucial to cell division during the mitotic phase.

Kinetochore

Each sister chromatid has this structure to which microtubules attach.

Surface area to Volume ratio (S/V)

When this ratio is small, cellular exchange is difficult, leading to cell death or division.

Genome to Volume Ratio (G/V)

As this ratio decreases, the cell exceeds the ability of its genome to produce needed proteins.

Prophase

Chromatin condenses into chromosomes and the nucleus disassembles.

Metaphase

Chromosomes line up.

Anaphase

Microtubules shorten and each chromosome is pulled apart into two chromatids.

Telophase

Nuclear envelope reforms and chromosomes decondense back into chromatin.

Genetic Linkage

Genes closer together on a chromosome are more likely to be inherited together

Meiosis

Produces four, non-identical haploid daughter cells from one diploid parent cell.

Crossing Over

Non-sister chromatids of two homologous chromosomes exchanging genetic material.

Independent Assortment

Random orientation of homologous chromosomes producing gametes with different assortments of alleles.

Prophase I

Chromosomes pair up lengthwise through synapsis, forming tetrads.

Metaphase I

Homologous chromosomes are arranged at the metaphase plate

Anaphase I

Homologous chromosomes separate and spindle apparatus guides the chromosomes to opposite poles

Telophase I and cytokinesis

Homologous chromosomes are separated, and cytokinesis results in two haploid daughter cells.

Prophase II

Spindle apparatus forms and microtubules move chromosomes towards metaphase plate

Metaphase II

Sister chromatids are no longer genetically identical due to crossing over and Chromosomes lined up at metaphase plate

Anaphase II

Chromatids separate, moving towards opposite ends

Telophase II and cytokinesis

Nuclei formation and decondensing of chromosomes

Chiasmata

Pairs are physically linked through regions where crossover occurs

Synapsis

Occurs during prophase I. Where homologous chromosomes pair up lengthwise