Asexual Reproduction
Division of the cell nucleus, results in two daughter nuclei, each have the same number of chromosomes as the parent nucleus.
Asters
Clusters of microtubes radiating out from the poles in diving cells. The are present in animal cells, but not in cells of flowering plants and most gymnosperms.
Cell Cycle
Cyclic series of events in the life of a dividing eukaryotic cell; consist of stages of interphase, mitosis, and cytokinesis.
Cell Plate
The structure that forms during cytokinesis in plants, separating the two daughter cells produced by mitosis.
Centromere
Specialized constricted region of a chromatid; contains the kinetochore.
Chiasma
An X-shaped site in a tetrad marking the location of homologous chromatids previously underwent crossing over
Chromatid
One of two identical halves of duplicated chromosome.
Chromatin
The complex of DNA, proteins and some RNA that makes up some that makes up eukaryotic chromosomes.
Chromosomes
Structures in the cell of a nucleus, composed of chromatin and containing genes.
Clone
a population of genetically identical organisms asexually propagated from a single individual.
Crossing Over
The breaking and rejoining of homologous (non sister) chromatids during early meitonic prophase 1, resulting in an exchange of genetic material.
Cytokinesis
Stage of cell division in which the cytoplasm is divided to form two daughter cells.
Diploid
The conditions of having two sets of chromosomes per nucleus.
Fertilization
Fusion of n gametes; results in the formation of a 2n zygote.
Gamete
A sex cell; in plants and animals, eggs and sperm.
Haploid
The condition of have one set of chromosomes per nucleus.
Interphase
Stage of the cell cycle between successive mitonic divsions; Its subdivisions are the G1 (first gap), S (DNA synthesis) and G2 (second gap) phases.
Karyotype
The chromosomal constitution of an individual
Kinetochore
Portion of the chromosome centromere to which the mitotic spindle fibers attach.
Meiosis
Process in which 2n cells undergoes two successive nuclear divisions, potentially producing four nuclei
Metaphase
The stage of mitosis, and of meiosis I and II; in which chromosomes line up at equator.
Mitosis
A type of reproduction involving only one parent (genetically identical offspring.
Prophase
The first stage of mitosis, meiosis I and II; chromosomes become visible as distinct structures, the nuclear envelope breaks down, spindle fibers form.
S Phase
Stage of interphase in the cell cycle during which DNA and other chromosomal constituents are synthesized.
Sexual Reproduction
Type of reproduction in which two gametes fuse to for a zygote.
Spindle
Structure consisting of mainly microtubes that provides the framework for chromosome movement during cell division.
Synapsis
The process of physical association of homologous chromosomes during prophase I
Telophase
Last stage of mitosis, meiosis I and II, when, having reached the poles, chromosomes become decondensed and a nuclear envelope forms around each group.
Tetrad
Chromosome complex formed by the synapsis of homologous chromosomes during meitonic Prophase I.
Zygote
The 2n cell that results from the union of the n gametes in sexual reproduction.