Meiosis in an Animal Cell

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Centrosome movement, spindle formation and nuclear envelope breakdown occur as in mitosis. Chromosome condense progressively throughout ______________________.
Prophase I
Each chromosome pairs with its homologous, aligned gene by gene, and crossing over occurs: The DNA molecules of non-sister chromitads are broken (by proteins) and are rejoined together.
Prophase I
Each homologous pair has one or more X-shaped regions called chiasmata, where crossover has occurred
Prophase I
Microtubules from one pole or the other will attach to the two kinetochores, one at the centromeres of each homolog. (The two kinetochores of a homolog, not yet visible abov, act as a single kinetochore.) The homologous pairs will then move towards the metaphase plate.
Prophase I
Pairs of homologous chromosomes are now arranged at the metaphase plate, with one chromosome in each pair facing each pole.
Metaphase I
Both chromatids of one homolog are attached to kinetochore microtubules from one pole; those of the other homolog at attached to microtubules from the opposite poles.
Metaphase I
Breakdown of proteins that are responsible for sister chromatid cohesion along chromatid arms allows homologs to separate.
Anaphase I
The homologs move towards opposite poles, guided by the spindle apparatus.
Anaphase I
Sister chromatid cohesion persists at the centromere, causing chromatids to move as a unit toward the same pole.
Anaphase I
When ______ begins, each half of the cell has a complete haploid set of duplicated chromosomes. Each chromosome is composed of two sister chromatids; both or one chromatids include regions of non sister chromatid DNA.
Telophase I and Cyokinesis
________ (division of the cytoplasm) usually occurs simultaneously with ________, forming two haploid daughter cells.
Telophase I and Cyokinesis
In animal cells, a cleavage furrow forms. (In plant cells, a cell plate forms.)
Telophase I and Cyokinesis
In some species, chromosomes decondense and nuclear envelopes form.
Telophase I and Cyokinesis
No chromosome duplication occurs between meiosis i and meiosis II.
Telophase I and Cyokinesis
A spindle apparatus forms.
Prophase II
In late ____________, chromosomes each still composed of two chromatids associated at the centromere, move toward the metaphase II.
Prophase II
The chromosomes are positioned at the metaphase plate as in mitosis.
Metaphase II
Because of crossing over in meiosis I, the two sister chromatids of each chromosome are not genetically identical
Metaphase II
The kinetochores of sister chromatids are attached to microtubules extending from opposite poles.
Metaphase II
Breakdown of proteins holding the sister chromatids together at the centromere allows the chromatids to separate. The chromatids move toward opposite poles as individual chromosomes.
Metaphase II
Nuclei form, the chromsomes begin decondensing and _______ occurs.
Telophase II and Cyokinesis
The meiotic division of one parent cell produces four daughter cells, each with a haploid set of (unduplicated) chromosomes.
Telophase II and Cyokinesis
The four daughter cellsare genetically distinct from one another and from the parent cell.
Telophase II and Cyokinesis