quiz Flashcards
hetero‐chromatin;
chromosome material of different density from normal (usually greater), in which the activity of the genes is modified or suppressed.
sister chromatid
either of the two identical copies (chromatids) formed by the replication of a single chromosome, with both copies joined together by a common centromere.
centromere,
the point on a chromosome by which it is attached to a spindle fiber during cell division
homologous
chromosome,
are chromosome pairs, one from each parent, that are similar in length, gene position, and centromere location
kinetochore
the place on either side of the centromere to which the spindle fibers are attached during cell division
spermato/oogonia
are both forms of gametogenesis, in which a diploid gamete cell produces haploid sperm and egg cells, respectively.
polar bodies
each of the small cells that bud off from an oocyte at the two meiotic divisions and do not develop into ova.
sperma/ootids
A haploid cell that results from the meiotic division of an oocyte and becomes a female gamete or an ovum
gametophyte
the sexual form of a plant in the alternation of generations. (haploid generation of plant life cycle 1n)
sporophyte
is the diploid multicellular stage in the life cycle of a plant or alga.(diploid generation of plant life cycle, 2n)
centriole
a minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division.
nucleosome
structural unit of a eukaryotic chromosome, consisting of a length of DNA coiled around a core of histones.
euchromatin
chromosome material that does not stain strongly except during cell division. It represents the major genes and is involved in transcription
When(inthelifecycleandinmeioticstages)ismeiosis
interruptedandresumedinhumanfemales?
Thus, in the human female, the first part of meiosis begins in the embryo, and the signal to resume meiosis is not given until roughly 12 years later.
