Cell Division Prt. 2 Flashcards
During meiosis,_____ cells, which contain a single set of chromosomes, are produced from a cell that was originally diploid.
haploid
Prophase I is further subdivided into periods known as
LepZygPachDipDiak
• Leptotene
•Zygotene
•Pachytene
•Diplotene
• Diakinesis
During the____ stage, the replicated chromosomes begin to condense and become visible with a light microscope.
leptotene
Unlike prophase of mitosis, the____ stage of prophase of meiosis I involves a recognition process known as synapsis, in which the homologous chromosomes recognize each other and begin to align themselves along their entire lengths.
zygotene
forms between the homologs. This complex is thought to promote the binding of homologs to each other.
synaptonemal complex
At______, the homologs have become completely aligned.
The associated chromatids are known as bivalents. Each bivalent contains two pairs of sister chromatids, or a total of four chromatids.
pachytene
involves a physical exchange of chromosome pieces that results in an exchange of genetic information. Depending on the size of the chromosome and the species, an average eukaryotic chromosome incurs from a couple to a couple of dozen ______.
Crossing over
By the end of the______ stage, the synaptonemal complex has largely disappeared. The chromatids within a bivalent pull apart slightly, and microscopically it becomes easier to see that a bivalent is actually composed of four chromatids.
diplotene
In the last stage of prophase of meiosis I,______, the synaptonemal complex completely disappears
diakinesis
, in which the spindle apparatus is completely formed and the chromatids are attached via kinetochore microtubules.
prometaphase
_____of meiosis I. the bivalents are organized along the metaphase plate.
However, their pattern of alignment is strikingly different from that observed during mitosis
metaphase
During__________ of meiosis I, the two pairs of sister chromatids within a bivalent separate from each other
anaphase
at___________ of meiosis I, the sister chromatids have reached their respective poles, and decondensation occurs in many, but not all, species.
The nuclear membrane may re-form to produce two separate nuclei.
telophase
The sorting events that occur during meiosis II are similar to those that occur during mitosis, but the _________is differ-ent.
starting point
the steps that occur during ______ of meiosis II are analogous to a mitotic division.
prophase, prometaphase, metaphase, anaphase, and telophase
