18 terms

Cell Cycle

Cell Cycle
Cycle in which cell grows, prepares for division, divides to form two cells
Prokaryotic Cell Cycle
Most of these cells begin to replicate chromosomes once they have grown to size; when replication is complete, division begins through binary fission
Binary Fission
Asexual reproduction; once chromosome has been replicated, two DNA molecules attach to diffferent regions of cell membrane; network of fibers form between them, pinch cell inward, dividing cytoplasm and chromosomes into to new cells
Eukaryotic Cell Cycle
G1, S, G2, M phases
Period between eukaryotic divsion; divided into G1, S, and G2
G1 Phase
Cell grows during this phase; increase in size and synthesize new proteins/organelles
S Phase
DNA replication; new copy of DNA is synthesized, so cell contains twice as much DNA at end of S phase
G2 Phase
Organelles and molecules required for cell division are produced; when completed, cell is ready for M Phase
M Phase
Cell division; includes mitosis and then cytokinesis
Chromosome divison; prophase, metaphase, anaphase, telophase
Genetic material inside nucleus condenses and duplicated chromosomes become visible; outside nucleus, spindle begins to form; nucleolus disappears, nuclear envelope breaks down
Area along length of DNA where duplicated strands are attached
Each DNA strand in duplicated chromosomes is referred to as chromatid; chromatids separate during mitosis
Fibers that extend from centrosome (of two centrioles); centrioles start to move towards poles of cell
Centromeres of duplicated chromosomes line up across center of cell; spindle fibers connect centromere of each chromosome to two poles of spindle
Begins when sister chromatids split up and move apart; continues as they move along spindle fibers to opposite ends of cell
Chromosomes, before distinct and condense, begin to spread out into tangle of chromatin; nuclear envelope reforms against cluster of chromosomes; spindle breaks apart, nucleolus form; mitosis is complete
Division of cytoplasm; in animals, cell membrane is drawn inward until cytoplasm is pinched into two nearly equal parts; in plant cells, cell plate forms halfway between divided nuclei, gradually developing into cell membrane and then cell wall