Chapter 7 - Cell Cycles Flashcards
What is binary fission?
Prokaryotic cell division-splitting or dividing into two parts.
What is the origin of replication (ori)?
A specific region at which replication of a bacterial chromosome commences.
What are chromatids?
One half of a replicated chromosome. Each chromatid contains one double helix of DNA.
What are chromosomes?
The nuclear unit of genetic information, consisting of a DNA molecule and associated proteins.
What is diploid?
An organism or cell with two copies of each type of chromosome in its nucleus.
What is haploid?
An organism or cell with only one copy of each type of chromosome in its nuclei.
What is ploidy?
The number of chromosome sets of a cell or species.
What are sister chromatids?
One of two exact copies of a chromosome duplicated during replication.
What is chromosome segregation?
The equal distribution of daughter chromosomes to each of the two cells that result from cell division.
What is a clone?
An individual genetically identical to an original cell from which it descended.
What is interphase?
The first stage of the mitotic cell cycle, during which the cell grows and replicates its DNA before undergoing mitosis and cytokinesis.
What is G1 phase?
The initial growth stage of the cell cycle in eukaryotes, during which the cell makes proteins and other types of cellular molecules but not nuclear DNA.
What is G2 phase?
The phase of the cell cycle in eukaryotes during which the cell continues to synthesize proteins and grow, completing interphase.
What is G0 phase?
The phase of the cell cycle in eukaryotes in which many cell types stop dividing.
What is prophase?
The beginning phase of mitosis during which the duplicated chromosomes within the nucleus condense from a greatly extended state into compact, rodlike structures.
What is a nucleosome?
The basic structural unit of chromatin in eukaryotes, consisting of DNA wrapped around a histone core.
What is a linker?
A short segment of DNA extending between one nucleosome and the next in a eukaryotic chromosome.
What is significant about 10 nm chromatin fibre?
The most fundamental level of chromatin packing of a eukaryotic chromosome, in which DNA winds for almost two turns around an eightprotein nucleosome core particle to form a nucleosome, and linker DNA extends between adjacent nucleosomes. The result is a beadson-a-string type of structure with a 10 nm diameter.
What is significant about 30 nm chromatin fibre?
Level of chromatin packing of a eukaryotic chromosome in which histone H1 binds to the 10 nm chromatin fibre, causing it to package into a coiled structure about 30 nm in diameter and with about six nucleosomes per turn. Also referred to as a solenoid.
What is a solenoid?
Level of chromatin packing of a eukaryotic chromosome in which histone H1 binds to the 10 nm chromatin fibre, causing it to package into a coiled structure about 30 nm in diameter and with about six nucleosomes per turn. Also referred to as a solenoid.
What is a mitotic spindle?
The complex of microtubules that orchestrate the separation of chromosomes during mitosis.
What are spindle poles?
One of the pair of centrosomes in a cell undergoing mitosis from which bundles of microtubules radiate to form the part of the spindle from that pole.
What is prometaphase?
A transition period between prophase and metaphase during which the microtubules of the mitotic spindle attach to the kinetochores and the chromosomes shuffle until they align in the centre of the cell.
What is kinetochore?
A specialized structure consisting of proteins attached to a centromere that mediates the attachment and movement of chromosomes along the mitotic spindle.
