Mitosis and Cell Division



phase of mitosis in which sister chromatids separate and are pulled to the opposite poles of the cell


abnormal number of copies of a particular chromosome


programmed death of cell, including destruction of its DNA and organelles

astral microtubule

spindle fiber that attaches the centrosome to the cell membrane

binary fission

process by which prokaryotic cells divide; asexual reproduction

cell cycle

life of a cell, from its beginning to the time when it divides to produce a new cell

cell division

process by which one cell divides and becomes two new cells

cell equator

imaginary line in the center of a cell during mitosis, along which sister chromatids align

cell plate

partition that forms along the midline of a dividing plant cell

cell-cycle control system

series of checkpoints directed by chemical signals in a cell that regulate cell growth and division


point on a chromosome that attaches to the spindle fibers with a kinetochore during cell division and at which sister chromatids are attached


structure in the cytoplasm of animal cells that coordinates the formation of microtubules, which allows cell division to proceed during reproduction


one of two identical halves of a replicated chromosome

cleavage furrow

indentation in an animal cell along which cytokinesis occurs


protein that helps bind sister chromatids together at the centromere


protein that helps condense DNA into chromosomes during prophase of mitosis


regulatory molecule that functions as a gatekeeper, along with cyclase-dependent kinases (Cdks), to move a cell past checkpoints in the cell cycle

cyclin-dependent kinase (Cdk)

regulatory molecule (usually a protein) that functions as a gatekeeper, along with cyclins, to move a cell past checkpoints in the cell cycle


pinching off of the cytoplasm to form two new cells at the end of mitosis


collectively the G1, S, and G2 phases of mitosis, in which a cell grows, replicates its DNA, and grows again

interpolar microtubule

spindle fiber that extends from one centrosome to the other across the cell equator


group of proteins bound at the centromere to which the spindle fibers attach


phase of mitosis in which the sister chromatids line up along the cell equator


process of cell division that results in two cells that are genetic clones of the parent cell

mitotic spindle

bundle of spindle fibers attached at one end to the centrosome

origin of replication

place on a chromosome where DNA replication begins


having more than two paired sets of chromosomes


phase of mitosis in which the nuclear membrane breaks down and spindle fibers attach to the centromere


phase of mitosis in which sister chromatids condense, the mitotic spindle begins to form, and centrosomes segregate to opposite poles


small piece of cell membrane used to transport materials within a cell