4-3 Vocab Flashcards
(20 cards)
Gametes
A haploid reproductive cell, such as an egg or sperm, that is formed by meiosis or is the descendant of cells formed by meiosis. Gametes unite during sexual reproduction to produce a diploid zygote
G2 Phase
The second gap, or growth phase, of the cell cycle, consisting of the portion of interphase after DNA synthesis occurs
Mitotic Spindle
An assemblage of microtubules and associated proteins that is involved in the movement of chromosomes during mitosis
Metaphase
The third stage of mitosis, in which the spindle is complete and the chromosomes, attached to microtubules at their kinetochores, are all aligned at the metaphase plate
Benign Tumor
A mass of abnormal cells with specific genetic and cellular changes such that the cells are not capable of surviving at a new site and generally remain at the site of the tumor’s origin
Telophase
The fifth and final stage of mitosis, in which daughter nuclei are forming and cytokinesis has typically begun
Density-dependent Inhibition
The phenomenon observed in normal animal cells that causes them to stop dividing when they come into contact with one another
Genome
The genetic material of an organism or virus; the complete complement of an organism’s or virus’s genes along with its noncoding nucleic acid sequences
Prometaphase
The second stage of mitosis, in which the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the chromosomes
Sister Chromatids
Two copies of a duplicated chromosome attached to each other by proteins at the centromere and, sometimes, along the arms. While joined, two sister chromatids make up one chromosome. Chromatids are eventually separated during mitosis or meiosis II
Chromatin
The complex of DNA and proteins that makes up eukaryotic chromosomes. When the cell is not dividing, chromatin exists in its dispersed form, as a mass of very long, thin fibers that are not visible with a light microscope
Malignant Tumor
A cancerous tumor containing cells that have significant genetic and cellular changes and are capable of invading and surviving in new sites. Malignant tumors can impair the functions of one or more organs
Centromere
In a duplicated chromosome, the region on each sister chromatid where it is most closely attached to its sister chromatid by proteins that bind to the centromeric DNA. Other proteins condense the chromatin in that region, so it appears as a narrow “waist” on the duplicated chromosome. (An unduplicated chromosome has a single centromere, identified by the proteins bound there)
Cell Plate
A membrane-bounded, flattened sac located at the midline of a dividing plant cell, inside which the new cell wall forms during cytokinesis
G0 Phase
A nondividing state occupied by cells that have left the cell cycle, sometimes reversibly
Cell Division
The reproduction of cells
Prophase
The first stage of mitosis, in which the chromatin condenses into discrete chromosomes visible with a light microscope, the mitotic spindle begins to form, and the nucleolus disappears but the nucleus remains intact
G1 Phase
The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins
S Phase
The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated
Mitotic Phase
(M) The phase of the cell cycle that includes mitosis and cytokinesis
