Chapter 8 Terms Flashcards
Life Cycle
The entire sequence of stages in the life of an organism, from the adults of one generation to the adults of the next
Genome
A complete (haploid) set of an organism’s genes; an organism’s genetic material
Asexual Reproduction
The creation of offspring by a single parent, without the participation of sperm and egg
Chromosome
A threadlike, gene-carrying structure found in the nucleus of a eukaryotic cell and most visible during mitosis and meiosis; also, the main gene-carrying structure of a prokaryotic cell. Chromosomes consist of chromatin, a combination of DNA and protein
Sexual Reproduction
The creation of offspring by the fusion of two haploid sex cells (gametes), forming a diploid zygote
Cell Division
The reproduction of a cell
Binary Fission
A means of asexual reproduction in which a parent organism, often a single cell, divides into two individuals of about equal size
Chromatin
The complex of DNA and proteins that constitutes eukaryotic chromosomes; often used to refer to the diffuse, very extended form taken by chromosomes when a cell is not dividing
Sister Chromatid
One of the two identical parts of a duplicated chromosomes in a eukaryotic cell
Centromere
The region of a duplicated chromosome where two sister chromatids are joined and where spindle microtubules attach during mitosis and meiosis. The centromere divides at the onset of anaphase during mitosis and anaphase II during meiosis
Cell Cycle
An ordered sequence of events (including interphase and the mitotic phase) that extends from the time a eukaryotic cell is first formed from a dividing parent cell until its own division into two cells
Interphase
The period in the eukaryotic cell cycle when the cell is not actually dividing. Interphase constitutes the majority of the time spent in the cell cycle
Mitotic Phase (M Phase)
The part of the cell cycle when the nucleus is divided (via mitosis), its chromosomes are distributed to the daughter nuclei, and the cytoplasm divided (via cytokinesis), producing two daughter cells
Mitosis
The division of a single nucleus into two genetically identical daughter nuclei. Mitosis and cytokinesis make up the mitotic (M) phase of the cell cycle
Cytokinesis
The division of the cytoplasm to form two separate daughter cells. Cytokinesis usually occurs during telophase of mitosis. Mitosis and cytokinesis make up the mitotic (M) phase of the cell cycle
Prophase
The first stage of mitosis, during which the chromatin condenses to form structures (sister chromatids) visible with a light microscope and the mitotic spindle begins to form, but the nucleus is still intact
Prometaphase
The second stage of mitosis, during which the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the sister chromatids
Metaphase
The third stage of mitosis, during which all the cell’s duplicated chromosomes are lined up at an imaginary plane equidistant between the poles of the mitotic spindle
Anaphase
The fourth stage of mitosis, beginning when sister chromatids separate from each other and ending when a complete set of daughter chromosomes arrives at each of the two poles of the cell
Telophase
The fifth and final stage of mitosis, during which daughter nuclei form at the two poles of a cell. Telophase usually occurs together with cytokinesis
Mitotic Spindle
A football-shaped structure formed of microtubules and associated proteins that is involved in the movements of chromosomes during mitosis and meiosis
Centrosome
Material in the cytoplasm of a eukaryotic cell that gives rise to microtubules; important in mitosis and meiosis; also called microtubule-organizing center
Cleavage Furrow
The first sign of cytokinesis during cell division in an animal cell; a shallow groove in the cell surface near the old metaphase plate