During cell division, the DNA in eukaryotic cell's nucleus is coiled into very compact structures called _____________.
____________ proteins are generally involved in controlling the activity of specific regions of the DNA.
Chromosomes that determine the sex of an organism, and they may also carry genes for another characteristic
Cell division in eukaryotes that results in new cells with genetic material that is identical to that of the original cell.
Phase of cell division. During this phase, the nucleus of a cell divides. It can also be called the M phase.
Phase of interphase. During this phase, the cell grows, creates organelles and begins metabolism.
Phase of interphase. During this phase occurs DNA synthesis and the duplication of the centrosome.
Phase of interphase. During this phase, the cells exit the cell cycle and are alive and metabolically active, but do not divide. They don't copy their DNA and don't prepare for cell division. If they are damaged, they cannot be replaced. This does not always occur, but if it does, it's usually from G1 phase.
genetic material in interphase. It cannot be clearly seen because it is not tightly coiled.
First phase of mitosis. During this phase, the DNA molecules are shortened and condensed by coiling. Spindle fibers are formed during this phase.
nuclear membrane and nucleolus
Enzymes during prophase break down the_______________________ so they are no longer visible.
Second phase of mitosis. During this phase, the spindle fibers attach themselves to the centromeres of the chromosomes and align the chromosomes at the equator.
Third phase of mitosis. During this phase, the spindle fibers shorten and the centromere splits separating the two sister chromatids.
Fourth phase of mitosis. During this phase, the chromosome pairs are pulled to opposite poles of the cell. The nuclear envelope and nucleolus reform before the chromosomes uncoil. The spindle fibers disintegrate.
The pairing of homologous chromosomes, which does not occur in mitosis. It occurs in prophase I in meiosis.
During synapsis, the chromatids with a homologous pair twist around one another. Portions of chromatids may break off and attach to adjacent chromatids on the homologous chromosome. This process is called ___________________. It permits the exchange of genetic material between maternal and paternal chromosomes.
Process that occurs in each cell formed during meiosis I an is NOT preceded by the copying of DNA.
In the development of sperm cells, a diploid reproductive cell divide meiotically to form four haploid cells called __________________.
During cytokinesis I and cytokinesis II of oogenesis, the cytoplasm of the original cell is divided unequally between new cells. One cell, which develops into a mature egg cell, receives most of the cytoplasm of the original cell. As a result, one egg cell is produced by meiosis. The other three products of meiosis, called ____________, degenerate.
During mitosis, animal cells divide the cytoplasm by constricting the cell membrane in the middle to form a _________.