Meiosis Flashcards
What is Meiosis
process by which haploid cells are produced from a diploid cell
What happens in Meiosis I?
homologous pairs of chromosomes separate and become haploid cells
What happens in Meiosis II?
haploid cells divide and sister chromatids separate, forming 4 haploid cells
What is bivalent or tetrad
homologous pairs of sister chromatids lay next to each other to form this
What is Synapsis
the process of forming a bivalent and crossing over
What does the synaptonemal complex do
protein structure that connects homologous chromosomes during synapsis
what is crossing over
physical exchange of DNA between maternal and paternal chromosomes of the crossing bivalent to increase genetic variation
what is the chiasma
the arms of the chromosomes that is exchanged between maternal and paternal chromosomes
what happens during Prophase I of Meiosis I
chromosomes condense, bivalents form, nuclear membrane break down
what happens during Prometaphase I of Meiosis I?
nuclear envelope completely dissociates, bivalents became attached to kinetochore microtubules by the spindle apparatus
what happens during Metaphase I of Meiosis I?
bivalents align in the middle of the cell as a double row, each pair of sister chromatids are attached to one pole
what happens during Anaphase I of Meiosis I?
connection between bivalents break, homologous pair separate, sister chromatids are pulled to their respective poles
what happens during Telophase I and cytokinesis of Meiosis I?
sister chromatids have reached their poles, decondense, and nuclear membranes form via cleavage furrow making 2 daughter cells
what happens during Prophase I of Meiosis II?
sister chromatids condense, spindle starts to form, nuc
what happens during Prometaphase II of Meiosis II?
nuclear envelope completely dissociates, sister chromatids attach to spindle using kinetochore microtubules
